Monsoon picking up over Southwest; heat & moisture across much of CA

Filed in Uncategorized by on July 2, 2017 2,949 Comments

A very hot start to California summer (except for the immediate coast)

Summer has been off to a very hot start across nearly all of CA away from the immediate coastline. (WRCC)

After a relatively mild spring across most of California, June brought quite the reversal. A prolonged, record-breaking, and unusually “muggy” heatwave enveloped nearly all of California for multiple weeks, and temperatures have only fallen back to average over the past few days. This remarkable early-season heatwave set innumerable daily temperature records across the American Southwest, tied or broke several June monthly records, and actually exceeded or tied the hottest temperature on record at a handful of sites (including Needles, CA and Las Vegas, NV). The very prolonged nature of the heat, combined with the presence of an unusually humid airmass over Northern California, made the human impact of the heat even worse–and also led to consecutive “hot day” and record warm overnight temperature records being set in a number of locations.

Interestingly, this searing heat did not quite make it all to the way to the Pacific coast–and while coastal areas in the Bay Area and Los Angeles area were still warmer than average, the lack of sustained offshore flow and the presence of relatively cool ocean surface temperatures allowed these regions a very localized reprieve from the extreme heat. This “cool coast/hot inland” setup is most pronounced during California heatwaves occurring earlier in the calendar year, when coastal upwelling tends to be strongest and when the natural “air conditioning” provided by the marine layer is at its most effective. Autumn heatwaves, on the other hand, tend to be characterized by stronger offshore flow and are more “isothermal”–with similarly hot temperatures occurring far inland and at the immediate coast.

 

Western ridge rebuilds; heat & and monsoonal flow commence

Strong high pressure will set up shop in a classic summer monsoon position over the interior Southwest in the coming days. (NCEP via tropicaltidbits.com)

It does appear that Western heat will make a return this week. This, time, as the western ridge builds, middle atmospheric winds will turn toward the southeast over California–opening the door for a substantial influx of monsoonal moisture for the first time this year. As anticyclonic circulation strengthens in the coming days, afternoon thunderstorms will develop to an increasingly widespread degree over the deserts of northern Mexico and southern Arizona, the remnants of which will eventually move from east to west over Southern California. This is a classic early monsoon pattern, and it’s one that the global weather models can capture well at the large scale, but the details are usually rather hard to discern more than a couple of days in advance.

At the moment, it does appear that Southern (and possibly central California as far north as the Bay Area) may be in a generally favorable position to see occasional pulses of moisture and mid-level atmospheric instability over the next 2 weeks. This will probably lead to bouts of widespread mountain and desert thunderstorms, and probably at least a couple of shots at isolated thunderstorms across coastal areas. The timing is impossible to pin down at this point, as weak mesoscale disturbances rotating around the 4-Corners High will dictate the highest likelihood of thunderstorms. As usual, there will be some fire weather concerns associated with dry lightning (especially in the wake of our big heatwave).

Monsoonal moisture will likely overspread much of California in the coming days, leading to mountain and desert thunderstorms. (NCEP via tropicaltidbits.com)

The upcoming heatwave won’t be nearly as intense as the last one, although it will still be quite hot away from the coast (and increasing humidity across Southern California may yield increasingly “muggy” conditions as well). There is a bit of uncertainty at the moment regarding how long the strong western ridge will persist. But there are indications that it will be pretty long-lived–and may yield a prolonged 2+ week period of relatively hot conditions and somewhat frequent opportunities for monsoonal moisture and associated convective activity (especially mountains and deserts). It’s that time of year!

 

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  • 82/83 El Nino baby (San Jose)

    I know we track total acreage burned via fires every year, but do we know the average number of distinct fires? Seems like there has been a lot of fires this year considering we have not had much dry lightning events. I know its hot, but still seems like they are popping up everywhere with no cause.

    • rob b-Truckee/East Bay

      I believe Cal Fire has said they’re have been more fires this year going back to Jan 2017.

    • Admode (Susanville)

      I just googled it: https://en.wikipedia.org/wiki/2016_California_wildfires

      https://en.wikipedia.org/wiki/2017_California_wildfires

      Not sure how up to date the 2017 page is but I included the 2016 page for reference.

    • alanstorm

      Well, there’s a HUGE uptick in tourist travel this summer. It’s been years since I’ve seen so many travelers pulling 5th wheels up hwy 101. The hiways to the country are clogged every weekend
      Most of the fires so far up here in Mendocino County have been auto-related. Cigarettes, dragging chains or car fires

      • 82/83 El Nino baby (San Jose)

        Great points.

    • Amy Cohen

      A few years ago, I was hiking in the foothills around the Caughlin Ranch area in Reno on a hot + windy summer day. Out of nowhere, a bush several feet in front of me ignited and quickly grew into an out of control fire. I had a brief moment to inspect the cause before sprinting to my car to call 911. Somebody decided to toss a bathtub upside down into the sagebrush along with several paint cans to avoid taking a trip to the dump and paying for it. The weird rubber like material used to insulate a tub during installation is what ignited. So, I think spontaneous combustion is the cause of many of these fires. Imagine how many people throughout corrupt and criminal infested California simply decide to drive into the mountains and dump their garbage instead of properly taking it to the dump? They can instantly get rid of their problem and make somebody else deal with it.

      • Dan the Weatherman

        I wonder how often pieces of glass on dry brush can ignite fires? This would be similar in a way to the interior of a car getting really hot with all the windows rolled up.

      • Bombillo1

        Well, at the risk of getting Daniel really fired up, there should not be dump fees (unless construction related). Having to fork over $40.00 to get rid of junk is very disincentivising. Should be sales tax supported.

    • jeff anon

      since there is a lot more annual grasses this year it is easyier for fires to start and makes them move much faster. the last 5 years have been lacking the amount of annual grasses

  • Cap’n

    I’m ready for my daily dose of destruction; any Twitter fire updates? Smoke has really pushed back in this afternoon. Hey Mathew I hit the motherlode of free wood over by Blue Coyote, heading over to get my second load. There’s at least 2-4 cords still oh lodgepole and Jeffery rounds. Pine Cone under the power lines.

    • AlTahoe

      They just cut down some trees here on the college campus and sent out this message this morning.

      “Hi Everyone,
      The trees have been cut
      down over the last couple days. Whatever wood is still laying on the ground
      near the cut sites is free for the taking, first come first served. Most of the
      wood should be near the corner of Incline Way and country club drive.”
      Thanks!

  • Thunderstorm

    A question for everyone that lives in the Sierras. A weak low is supposed to set up off the coast of northern California next week and linger for awhile. Does this low in the summer bring higher winds to the area.

    • AlTahoe

      Yes. A low even entering Oregon like this previous Monday and Tuesday really gets the wind cranking up here.

      • Thunderstorm

        Hope that they have a meteorologist on the Detwiler Fire that will know about this and they have a plan.

    • Yeah.

  • Craig Matthews

    As a temporary side-step comment to the ongoing fire/heat/warming situation….Here’s some years I’ve found on the ESRL Plotting and Reanalysis site in regard to “potential similar” SSTA gyre analogs for later this year into the next. Lot more to consider then just SSTA of course. But will be interesting to see how this year’s SSTA evolution plays out across the board. https://uploads.disquscdn.com/images/b1c3d77f759adee989545f64801feb2ef0b8990b6a54eaa8e5364bf21acce878.png https://uploads.disquscdn.com/images/e25514fdef5fc3baef560c318c56eb06d2d667c01519fba9bc242a2c56e00dd4.png https://uploads.disquscdn.com/images/bcdeff032e36805d825054c29087081646bbdeca79abe03cddf91ea96d9d4c8f.png

    • Craig Matthews

      1980-81, 1993-94, 2003-04, and 2005-06 wouldn’t post, bummer, but they look similar SSTA wise as well… will try posting later if anyone is interested….now back to the regular schedule..

      • Yeah I’m interested of course. I’ll mention a fairly positive MEI currently to maybe change your thoughts? I’m not buying a LaNina. Selling her short to CFS. LOL
        I’m still wondering if there’s still another year of blow-off from 15-16? The Atlantic may still fire up some hurricanes. The EQ EPAC is all manic again. Kinda like what is expected in a developing +ENSO

        • Chris

          The winds south of these hurricanes is westerly too. ….

        • Craig Matthews

          Always interested in your inputs..esp your atmospheric addys MEI winds etc. I’m leaning toward a cocktail mix of 2003-04, 19443-44 and a bit of 2005-06. Right now, I’m particularly interested in 1943-44, 1993-94, and 2003-04 atmosphere corr to their ssta gyres, so any addy as far as winds and pressure variance data for those years, or other ones you find is most welcome from ya. Check out 2003-04, notice the IO ssta was in a weak +IOD like gyre, and ssta was relatively flat between west and east tropical pac with a couple of patches of neutral in the middle. At this time a 2003-04- like ssta gyre would seam more likely, being the vast +ssta, the depth of negative anomalies below the surface of the eqpac( or how far down those negative values are below the +ssta at the surface and just below in the centra-eastern eqPac). However it is a question of where the atmosphere takes it from here. Recently, there has been a tremendous convection amp in the Indo-WPac which could create a snap back Nina atmospheric response the next few weeks at least depending on what the wave does. If we get a strong long lasting trade surge over the eqpac, re-occurring into the fall, then I also think it is possible to see neg values show in the eastern eq pac surface flowing toward the central eqpac, giving ssta gyre like late 1993 or late 2005, or cool ssta epac – warm west. But if weaker trades I think 2003-04 is more likely. More years to explore tho. And need to look into MEI/SOI, etc is a must! Anyway here’s 1993-94 and 2003-04, with 2003-04 being the closer to potential IMHO. https://uploads.disquscdn.com/images/1a35332d7cba7f494b7c11eaf50cb8f0186478b947ae20f9129565cd320e1b6f.png https://uploads.disquscdn.com/images/1a35332d7cba7f494b7eaf50cb8f0186478b947ae20f9129565cd320e1b6f.png https://uploads.disquscdn.com/images/10e0028a8838b1dca6267c1367c675a1f2073eea81141fb1984796fefef57ad1.png

          • Craig Matthews

            Adding on to the bottom of your comment irt eqpac manic…possible being pre +ENSO like. Paul Roundy mentioned something like that as well. He mentioned fall 1994 🙂

          • jstrahl

            Fall ’94? We know how ’94-5 turned out.

          • Craig Matthews

            Here’s the VP signal over the Indo-far WPac I mentioned as a strong convective amp. Looks HUGE!! This will no doubt impact the trades as the potential is highly elevated for increased east to west atmos. grads across the tropPac domain as the pressure lowers, potentially a lot, in far WPac. Some models progress that signal into wpac which would be interesting. https://uploads.disquscdn.com/images/b343aad1d5c4a410db3a05ed48567f9f87d70c593a60ac597e359cd3a643e670.gif

          • Get me an analog that has cooler water over Hawaii and a wee bit north and east…. 🙂 With weak/neutral the atmosphere doesn’t connect so that’s what I’d zero in on. (Atmosphere similarities with those analogs) I’m running out now. Sorry I can’t reply with a more complete answer. Just have time to type from the hip, per se.

      • jstrahl

        2005-6 is quite different from the others, at least regarding Bay Area rain totals, the first 3 were below to slightly below average, the last was well above average.

    • 805 Weather (Camarillo)

      Super wicked post Craig!

  • AntiochWx

    18z doesn’t quite have the intensity the 12z had, so that is a start. Hoping 00z runs show some mercy.

  • AntiochWx

    So at least the 18z isn’t as intense as the 12z was, hopefully the 00z isn’t as relentless with the long range ridge.

  • Thunder98

    I predict that most of California will see yet another wet winter ahead. This is my 1st prediction and I will revise and will add more details as time goes on.

    • Steve Lutton

      Well, I’m on your side so I agree.

    • Great Winter of 2017 (SMC)

      That is my prediction as well, but not as wet as this last year. I’m thinking anywhere from 125%-175% percent of average for California

      • Cap’n

        I’ll take 117% average but colder.

    • Pfirman

      Let me know when you have reached ‘dry winter ahead’, aka revised prediction number 121.

      • Tuolumne

        I prefer retrodicting. Much less stressful and I can even quote exact rainfall figures.

  • Thunder98
  • 805 Weather (Camarillo)

    Terrible news. & it may only just be the beginning… https://twitter.com/abc7/status/888230854585073668

    • Cap’n

      Oh no. So are we thinking it’s made it’s way into downtown Mariposa or maybe these are areas on the outskirts? What a bummer. I think this fire season is just going to be horrible.

    • Pfirman

      That photo is very disturbing.
      What is that guy doing there? Running? What are those high weeds doing there? What are those people doing living there?

      • inclinejj

        He looks like a fire fighter to me.

        • Pfirman

          Of course, but what is doing? Or what was he doing? I don’t recognize what he is carrying either.

          • SBMWill

            Maybe checking if anyone was inside or if any pets bad been left behind. Assessing the property before its destroyed for a post fire report? Not sure if those guys can disconnect power or gas in some way. Obviously I’m not an expert. But clearly there was an extreme lack of property weed abatement going on. Looks like the place may be abandoned.

      • Admode (Susanville)

        He’s carrying a drip torch, man. He lit that fire to protect that structure. The sucking of the main fire plus favorable winds will drive that back burn towards the main fire before the energy of the main fire gets to the house.

      • Admode (Susanville)

        There might be some tall weeds on the back side of that house but if you look closely you can see that there has been a lot of prep put into where he’s walking.

    • Great Winter of 2017 (SMC)

      This looks really bad and is reminiscent of the Rim Fire. If the fire is growing at the rate it has the last couple days ( 20-30 k everyday) it could be 100 k acres by morning. This jump in destroyed homes makes me think that it has finally started affecting the main town of Mariposa

  • AntiochWx

    So far I like 06-07 as my analog. I’m thinking this winter will be slightly below average temperatures with 85-100% of precipitation.

    • Craig Matthews

      I’m leaning to those percent numbers as well, yet hopeful for more precip then that, especially for socal.

    • Pfirman

      Well, do come back next spring and let us know how much crow you have to eat. Of course, met folks never look back.

      • AntiochWx

        Heh, I’ve always been the humble type. I will always come back right or wrong, it makes no difference to me. Long range forecasting is all an educated guess anyways.

        • Pfirman

          Ok, change ‘crow’ to ‘humble pie’.

      • AntiochWx

        I wish I was a met, I have some met and climate education from the penn st university, but I never finished the major and switched. I passed calc 1, but immensely struggled with multivariable calculus.

        • Pfirman

          I hear you brother.

        • jstrahl

          I could’ve helped. 🙂

          • AntiochWx

            Maybe maybe not, I had a few tutors in college, and it just seemed I could not grasp it. It might be because I easily forget things, I swear I will learn it then forget it months later.I will probably give it a shot again sometime or other, weather is like my drug, I can’t get away from it and I hate not being able to do it for a job.

          • jstrahl

            My experience of over 25 years in tutoring and teaching multivariable calculus is that students really need a general understanding of why it’s being done, what the applications are, if they are to make any sense of it, and most of the time the theory is taught before any of the applications are brought in, as “word problems” or numerical problems.

    • SBMWill

      Your funny making predictions. One thing I now understand about weather and our future is all predictions are wrong.

      • AntiochWx

        What is so funny about it? Please don’t feel that way, there is a lot of science that indicates it isn’t all guess work. Especially climate, because climate can be predicted because of variables that are known to increase temperature. See physics on black body radiation and thermodynamics. We know if a planetary body has a higher concentration of greenhouse gases, its overall temperature will increase. Long long term climate changes are based on Milankovitch cycles.

        • jstrahl

          Temperature is but one of several hundred variables involved, many of which are hard to measure if not downright impossible, and many of which are not even known, i.e. unknown unknowns. Long term predictions based upon CO2 content are quite possible, that’s climate. But climate is not the same as weather, which is short range.

          • AntiochWx

            Right, that is where I was getting at. Weather predictions do not equal climate predictions as some people confuse. Climate predictions can generally be predicted because of the nature of its input/output type system. We know greenhouse gases, TSI, and volcanic activity are the primary climate drivers other than the Milankovitch cycles. Weather because of its short term variability and caos will always be generally difficult to predict because like you said has so many variables.

        • SBMWill

          Agree to disagree

          • AntiochWx

            You could at least tell me why you disagree, I’d like to at least hear your reasoning, whether we agree or not.

          • SBMWill

            Ha ok you want some dialogue. Well I am not anti science in any way and your right. Predictions are just what they are essentially educated guesses and maybe we are getting better at making these guesses. My point is only that the factors at play are unpredictable at least at this fairly archaic time in our development. I agree Weather can be predicted with some accuracy at least 5 days out. Your probable at lot smarter than me and I completely wrong. I would also add I do not assume anyone shares my beliefs or opinions they are mine yours are yours. Keep up your search for knowledge and truth(if that exists) because our brothers and sisters have there heads in the sand.

          • AntiochWx

            At least you are open to science, you would be surprised by how many people are out there that won’t even listen to and fail to believe in concrete evidence. Predictions are really just educated guesses, but that doesn’t make the science invalid like a lot of people think. Scientists are just highly educated people that are experts in their field of learning, we are still human and don’t know everything. Yes accuracy is there most of the time within 5 days, but really its all about probabilites. I may or may not be smarter than you, but that doesn’t really matter, I never think I’m better than someone else just because I may have more knowledge, I try and share what I do know, or what I think I know. Honestly, now we are getting into philosophy, what is true and what is knowledge. Me personally I try and stick to science, what is observable and real. I just feel bad for people how don’t want to listen, because science doesn’t stop even if you don’t believe in it.

    • Tyler Price (Carmel Valley)

      Oh yeah, well I predict this next winter to be a whopper of a winter with deluge after deluge a storm season of epic proportions!! ??? it’s gonna be a repeat of 2017 winter except this time SoCal gets in on more of the action as well! I predict above average precipitation for NorCal and SoCal!

      • AntiochWx

        Not to be rude, but what are you basing your prediction from other than wishcasting. You have specific weather analogs or scientific logic? Just curious to hear your reasoning, and others for that matter who think it will be a repeat of last year.

        • Cap’n

          We do this every year, we wishcast and flip coins to predict the coming season and then post our findings here on the World Wide Web.

          • AntiochWx

            but where is the science in that? I don’t do voodoo and healing crystals. I need substance.

          • Cap’n

            I hear you. But after I’ve analyzed all of the data and the charts, I still like to line up my 45 bobbleheads on the window sill of my shed and drip candle wax over each one. Whoever is the last standing will then tell me what to expect come winter.

            It’s a guilty pleasure.

          • AntiochWx

            Don’t get me wrong, its ok to have some guilty pleasure, but I try and keep my rational to science and mathematics as much as possible. I once tried my hand in blackberry, acorn, and wooly caterpillar winter analysis. I guess that is as guilty pleasure as I get I suppose.

          • Crouching Dallas

            Couldn’t have picked a better time to log back into WeatherWest. Cheers to you and your bobbleheads, Cap’n.

          • Cap’n

            Good to see you on here. I figured you had runoff with Jackie Johnson into the sunset…

          • Crouching Dallas

            Blondey wife and I took an epic trip to the Cascades. So…kind of?

          • Pfirman

            Figured something was off. That’s three too many bobbleheads.

          • We’ve been missing some real good prose here. Raise one from the dead.

          • 82/83 El Nino baby (San Jose)

            We’re you on here the last few years. If you went with the “science”, the 2016 El Nino was supposed to cause a deluge and 2017 was going to be very dry. We know how that turned out.

          • 805 Weather (Camarillo)

            Not everybody forecasted the same thing for 15-16 & 16-17, however a general idea was proposed & it went south pretty quickly.

          • AntiochWx

            Statisically speaking, El Ninos , especially strong El Ninos have historically produced wetter than normal conditions, the science is there but it like anything is still subject to probabilities. The RRR had a lot to do with it, and unfortunately with changing global SSTs and the expansion of the hadley cells, new semi permanent features will start to overwhelm certain atmospheric indicators.

          • jstrahl

            Eh? There was no RRR in 2015-16.

          • Hadley Cell did not cooperate as the models thought it would. If it had, SoCal would have had been in the game BIG time. SST’s IMO were way too warm in Nino4 which was why Nino 3.4 set a record. If Nino3 and Nino1+2 had anomalies that were warmer than Nino3.4 and 4 The beast would have delivered.

          • AntiochWx

            In the true sense of the RRR which was mostly 2013-2015, I’d say no, but as Pluvious said, the Hadley Cell was not cooperating.

          • Charlie B

            Remember February 2016? It might not have been a classic RRR, but that month featured 12 days of bone dry warmth with then one moderate mid month storm and then another two weeks of dry warmth.

          • 82/83 El Nino baby (San Jose)

            True, but that is based on less than a handful of events. I don’t think its enough data for scientists to claim as they did, with almost absolute certainty, that it would results in above average rains for CA. The RRR had been around for multiple years so why did they not consider it when making predictions for El Nino 2016?

            I do not expect scientists to have all the answers or to be perfect. I just don’t think there is anything wrong with saying “we don’t know” or “the data is not giving us a clear indication”.

            Wildly wrong seasonal outlooks help the naysayers of climate change as they use a terrible seasonal outlook as proof that if scientists can’t tell us what is going to happen in a few months, how can they claim to know what will happen in ten years?

          • AntiochWx

            I agree its a very small sample size, but that is really all scientist have to work with, so they made the best educated guess they could. I don’t think they were expecting the strong El Nino to be overwhelmed by other signals. It will make for a great case study. I do not expect scientist to have all the answers either, but I think they must feel pressured to deliever a forecast at all times, so they can’t just say we don’t know even if they feel there isn’t enough data for a high confident forecast, but I can’t speak on behave of those scientist. As for the climate naysayers they must realize weather forecasting and climate forecasting are 2 different methods. Weather is short to medium range forecasting over the span of 2 weeks to a few months in advance and are dealing with multivariables that even with the most minor fluctuations make forecasting extremely chaotic. Climate science forecasts are based on a planetary physical system that obey natural laws. We know a planetary body’s temperature is dependant on TSI (OLR), greenhouse gases, volcanic activity, and long term Milankovitch cycles, and can be mathematically calculated based on input/output on Earth’s atmosphere and solar radiation.

          • Thesaurus is adding all the contributors on this board as a synonym to the word motley when used as a noun. If you asked “What is a half dime?” You would get clever, sarcastic, silly, truth, and answers that contain dogs and certainly bobble heads. Your contributions are valued here by more than just an upvote

          • Cap’n

            Hey make a prediction with your charts and analogs that is actually even close to correct at some point and your jargon will finally be less nonsensical than bobblehead chatter.

          • I’m trying but it takes Rx drugs in the right combo.

          • Cap’n

            My comment was harsh. I had just come back from a competitive meditation/yoga class so I was frothing from the fingertips. Your comment got me going. I have a huge ego but at the same time I feel ‘less-than’. There is some great intelligent analysis on here and I definitely put you in that bracket. I sometimes lashout because the vast majority of it escapes comprehension due to my pea brain. In all honesty I guess I really don’t have much faith in anything at all.

            Please like me?

          • I didn’t give it a second thought. Have fun this weekend. 🙂

          • Tuolumne

            Wishcast is a great word!

        • Tyler Price (Carmel Valley)

          The weather wizard told me so! 😉

          • jstrahl

            Thanks for the good analysis, Tyler. We’ll see, but what you say does base itself upon pretty good logic.

          • AntiochWx

            I appreciate your input, this is all I ever ask of anyone. I like different opinions provided they have some logic to back them up. I agree with the PDO switch, it definitely looks to have switched, but the next few years will fully confirm it. I think the correlation is there with +PDO and warmer summers, I will have to look at some composites later. I still want to see more evidence on the RRR and its ability to overwhelm the ENSO conditions. If it comes back this winter or even next, we can start to really be concerned because it means it maybe a sign of a more semi-permanent feature. Traditionally neutral and El Ninos have boded well for California, but I’m not sold until I see the RRR having less influence in our winters.

          • alanstorm

            So what was the deal with the consistently flaccid/loopy JETSTREAM during the RRR’s rein?
            Was it-
            A….. abnormally weak meridional flow gave rise to or allowed the formation of a RRR/omega on steroids (with enhancement from a self-reinforcing feedback loop in the form of a GOA BLOB on steroids)
            OR…
            B….the Pacific JET was re routed to Alaska every Jan-Feb during this period BECAUSE of the RRR on steroids with BLOB inhancment?
            OR….
            C…..all of the above

            Layman here-
            Chicken or egg question really. Who made who?

            & who’s supplying the steroids?

          • AntiochWx

            In short, AGW is the main cause of consistently loopy jetstream. As the global temperature gradients weaken, this allows for the jetstream to meander more. Just like a flowing body of water, when there is a lower gradient, the river meanders and slows down, the atmosphere is no different. This is the primary reason for the theory of increased extreme weather events with AGW. It is also because of the expansion of the hadley cell, which is also caused by AGW, so in short alot of the recent weather weirdness is just the beginning affects from AGW. The natural variability still exist in our typical weather patterns, but with the help of AGW, it enhances stagnation and persistency of troughs and ridges. I definitely recommend reading and watching all of Dr. Jennifer Francis’s research.

          • alanstorm

            Yep. I’ve been aware of her work on the “meandering loopy jet”, three words I’ve been saying on this forum for the last 3yrs with subsequent eyerolls.
            To add to the comparison : a steeper temp gradient is like a steep canyon where that river (jet) flows stronger with more velocity.
            WHAMMO. Good bye RRR.
            But wait- what happened last winter with the record rains & strong zonal jet? A few times it was stretched all the way to Japan!
            Did the Arctic suddenly cool back down?
            Another stuck extreme pattern?
            SO.. the Chicken (GW) laid an egg, which hatched as a Loopy Jet.
            Loopy Jet laid its own egg, the RRR.
            Just my uneducated question.(s)

          • AntiochWx

            Its not that it laid an egg so to speak, but natural variability still exist. You can still get a strong jet flow, but GW just makes naturally loopy patterns even more loopy and persistent than they otherwise would be. Its all rooted in physics, the temperature gradients weakening due to GW is very sound physics. It works both ways really, a troughy pattern can get stuck and persist, its why I call it the TTT (Terribly Tenacious Trough). Statistically the world will see more RRR and TTT events, as long as AGW persist. Scientist are still trying to figure out what will happen in the event the arctic sea ice melts out completely during the summer months, with the lack of high albedo the ice causes could enhance the weather weirdness.

    • Dan the Weatherman

      I wouldn’t want a repeat of 2006-07 for Socal, though! It was absolutely BONE DRY in Socal that season, with Los Angeles having its driest season on record of a measly 3.21″ from July 1, 2006 to June 30, 2007. 2006-07 wasn’t a warm year like 2013-14 or 2014-15, and as a matter of fact there was quite a cold snap in mid-January that did a fair amount of damage to ornamental landscape plants, especially in the Inland Empire.

      If anyone knows why 2006-07 was so dry for Socal, feel free to comment. I know it was a fairly average year in Norcal. I had more rain here in Orange from May to September 2015 than I did for the entire 2006-07 season!

      • AntiochWx

        I’m not rooting for a repeat of 06-07 either, its just what I think may happen given some of the conditions that are occuring now and similarities in ENSO pattern as I outlined in my graphic I posted. I wasn’t going based on the whole year of temperatures for 06-07, only was basing it on summertime temperatures in 06, mainly June and July. I’m not sure how August will turn out, ultimately depends if the 4 corners high will shift enough to let the offshore trough to dig in.

      • AntiochWx

        The more I look at it, the more 04-05 does seem to fit as well.

      • weathergeek100

        It’s incredible how dry that year was. 3.21″ for LA? One good storm can drop that much rain on the city.

      • AlTahoe

        That winter it didn’t snow in Tahoe until February and then we got like 10′ in 3 weeks. That was pretty much it for the entire winter.

    • AlTahoe

      I have been seeing this Analog and 2003-2004 coming up a lot and some mentions of 1981-1982.

      I am thinking that the mega block that setup shop over Alaska last winter will return again this winter in a slightly more westward location allowing for more cold snaps. The mega block tends to show up in consecutive years in the past. If moisture can undercut the ridge again and meet up with the cold air we could see good snowfall totals. I am going with 425″ of snowfall for the Donner pass snowfall site, and more snow than last year at South Lake Tahoe. We will break the 200″ mark for the first time since 2010-2011.

      • Cap’n

        What was the final tally for Central Sierra Snowlab on Donner ? I find it impossible to navigate that site and BA has disappeared. I’m thinking around 550″ or so.

        • AlTahoe

          Their Facebook page has a season total of 570″ which puts it around 18th place

          • Cap’n

            I was close! Ended up with 350″ down at 5,900 at our place, plus a whole bunch of rain.

      • jstrahl

        Those two seasons were quite different.

  • Great Winter of 2017 (SMC)
    • Pfirman

      It would be interesting to take the last ten years and ‘paint’ the areas of the state that have burned, with depth of color according to what has reburned over that timespan. Any idea as to what percentage of land would be covered?
      Then move on to the entire west.

      • PRCountyNative

        An arsonist’s treasure map!

      • alanstorm

        I think Lake County would be dark red/black

        • Pfirman

          I think you get my drift all too well.

      • Admode (Susanville)

        There are his maps that you can find which show fire history by decade. You can click on each fire and it will give you stats. Is that kind of what you mean?

        • Pfirman

          No, not fire history, per se,, but an indication of what has actually burned, statewide, over that period. I guess you would start with one year, and then overlay the next, until you had the whole span, with whatever reburned getting a deeper hue each year.

  • AntiochWx
    • AntiochWx

      Solidly neutral conditions. If I get time later, I will try and run composites of all the neutral ENSO years and neutral years coming off a previous El Nino.

      • 82/83 El Nino baby (San Jose)

        I think we are technically coming off a weak La nina, not an El Nino.

        • AntiochWx

          I meant within the last 2 years, in relative terms (moderate to strong) shouldn’t be vage in my discussions, I will tighten them up.

      • 805 Weather (Camarillo)

        Really enjoying the work you are putting into correlating analogs & discussing with others in a fair & honest manner.

        • AntiochWx

          I try to be as fair in my discussions as possible, I have no problem with differing opinions, I just want to see some rational discussions, afterall that is how we progress to more accurate predictions.

    • CFS hasn’t been dragging the bottom in quite some time. I don’t have time at the moment to compare last 4-5 years. I don’t remember off the top of my head it ever being in the bottom 1/2.

      • AntiochWx

        I’m not sure either, I generally don’t know where the models predicted what going back years. I do know you can find the overall skill scores ( for foreasting verifications) for each model, but I will have to look when I have time.

  • Pfirman

    From Daniel’s retweet…..if I may.

    ‘It’s a “cruel irony,” Frumkin said, that as
    the world gets hotter, we need more air conditioning, and thus consume
    more electricity. And if that electricity comes from fossil fuel
    sources, it will create more global warming, which in turn will increase
    the demand for air conditioning. The answer, he said, is to “decarbonize the electric grid.” But that’s
    easier said than done, especially when the Trump administration is
    devoted to increasing the use of fossil fuels to support the country’s
    electrical grid.’

    • PRCountyNative

      The rest of the world, led by China, is pledging to upgrade their national electric grids, then form a worldwide electric grid, powered by renewables.

      Geothermal from Iceland, sun for solar from the tropics and African desert, wind from all those windy places. Add in existing hydroelectric.

      The bigger the grid the less need for any storage. “It’s always sunny (and windy) somewhere!”

      At last report China said they were ahead of schedule on their national grid upgrade.

      • Pfirman

        Anybody remember Buckminster Fuller and his idea of a global energy grid?

        I have summarized
        my discovery of the option of humanity to become omnieconomically
        and sustainably successful on our planet while phasing
        out forever all use of fossil fuels and atomic energy
        generation other than the Sun. I have presented my
        plan for using our increasing technical ability to
        construct high-voltage, superconductive transmission
        lines and implement an around-the-world electrical
        energy grid integrating the daytime and nighttime
        hemispheres, thus swiftly increasing the operating
        capacity of the world’s electrical energy system and,
        concomitantly, living standard in an unprecedented
        feat of international cooperation.

        • PRCountyNative

          We’re not short on solutions. What needs to be done is known.

          That’s why i believe humans aren’t that special. To not do what must be done to ensure survival of the species, but rather act on behalf of the individual, is typical animal behavior.

          BF sounds like a smart guy.

      • Nathan

        Pledge*

        • PRCountyNative

          Starts with a pledge, words. China is acting, and ahead of pledged schedule (according to NY Times article on presentation to the UN a while back).

          Meanwhile the USA is pledging, saying, it will do no such thing, but rather go back to coal.

          Your point?

    • roseland67

      What Trump administration says they’re going to do and what they actually do, are rarely the same,
      (so far anyway).
      Time will tell

    • HighWater

      Go bark at China and India about there coal power plants. Geesh!!

      If Hillary were President she would have magically created power plants that run on unicorn horns to produce power and return the Earth back to her normal self

  • Great Winter of 2017 (SMC)

    The fires growth has been stunted an has only grown about 1,000 acres since yesterday. Stats: 74,000 acres, 15% contained, 3,700 personal on the fire, 1,500 structures threatened. They even go as far to say they are making a turn on the wildfire! This is the best news we got from the start of it. http://www.mercedsunstar.com/news/local/community/mariposa-and-yosemite/article162825563.html

  • Cap’n

    Another morning with the space heater on in the bathroom. 36F with a high of 82F predicted. Getting to be time for those huge August temperature swings in Truckee.

  • Thunder98
    • Dan the Weatherman

      I’m glad that is marine layer clouds and not smoke from yet another fire!

  • Finally looks like a decent monsoonal surge will actually occur on Monday/Tuesday. Will probably write an update on this, plus our very hot summer thus far, over the weekend. Also: long range, looks like there will be a pretty big hurricane west of Baja that will be in a somewhat favorable position for moisture advection into CA around the start of August…

    • Great Winter of 2017 (SMC)

      I have seen both of these things and I am extremely excited! http://www.tropicaltidbits.com/analysis/models/gfs/2017072106/gfs_mslp_pcpn_frzn_us_36.png

    • 805 Weather (Camarillo)

      YUP :D. All 3 models have a good agreement up until about 120 hours for our region.

      • 805 Weather (Camarillo)

        It appears to be a very slow moving easterly wave that slides up the GoC & Baja is pulled into SoCal by the recurring upper level low I have been mentioning that’s been sitting off SW of SoCal along with an incoming low caught in the flow from the GOA trough currently spinning up north. This low is sitting just east & north of 30N, 140W at the moment. These two lows will be the driver for how far the easterly wave’s energy makes it NW. Euro 00Z has the idea as well, however only the 700mb flow pattern stays east of the usual monsoonal points of SoCal (mountains, deserts.) However latest GFS trend has been showing this wave making it far enough west that it advects into the PNW. Likely a mixing of the two lows & the wave with the idea I mentioned above, going to be a tricky convective event if it occurs. Here is the triangle of lower heights over the state on the Euro… & then GFS latest run. https://uploads.disquscdn.com/images/d896d261a7e653c509a78ae4921522b44c569cafd845a7b098826ef734ebf050.png https://uploads.disquscdn.com/images/e956963c4621d2688cbc331b952a2c11f0b4f736133347103c6aaac7f26328ad.png

        It seems the easterly wave is advected more progressively by the northern low in the latest run of the GFS compared to the Euro having the southern low less progressive with the wave & the southern low having more influence. Euro 12Z will be interesting. Here is the northern low coming in out of the NPAC. https://uploads.disquscdn.com/images/9e88d1f27b02f8655e6cf5922a3e085a47fdb8b58c95794c49215298ec248c9b.gif

      • SoCalWXwatcher

        So far this season models haven’t handled these Monsoonal surges well, as the moisture has ended up not as far West as initially projected. The upcoming pattern does look interesting though, and hopefully we get to see some convection and T-Storms West of the mountains.

        • SoCal Al (El Monte-SGV)

          Totally agree, even Oxnard has mentioned the difficulty forecasting this season’s monsoon surges. Arizona has benefited greatly this season with the position of the HP center location more to the west as compared to previous years. Also, I believe the trough off the NW coast and it’s dry southwest flow has also been a factor for our very limited convection here in SoCal.

        • 805 Weather (Camarillo)

          I’m taking note of this one as much as I can, if the two lows do indeed form & stay stationary, that easterly wave will have an easy change to change it’s track… It’s gonna be a nail biter watching it move west.

    • Nathan

      Yaaaaay fires in socal!!! Yaaay monsoon.

    • Bob G (Gustine)

      If we could just have good cloud cover and some sprinkles in the valley from it I would be happy. It would break up the monotony of the summer weather we’ve had so far.

  • jstrahl

    Sorry if already posted, but this article has a very intense photo of the effect of the Mariposa fire on the Tahoe area. http://www.sfgate.com/news/article/Detwiler-Fire-Mariposa-smoke-Lake-Tahoe-sunset-CA-11303340.php

  • Great Winter of 2017 (SMC)
    • DelMarSD

      Dolores 2.0?

      • Dan the Weatherman

        I would like to see some summer rain / t-storm activity in coastal Socal like we saw in 2015.

    • happ [Los Angeles]

      To make this summer more like 2015. It has been humid and some great cumulonimbus build ups but no rain thus far.

    • 805 Weather (Camarillo)

      Unfortunately the frames you posted are two different hours & two different lows, however the low at hour 288 is the one that will likely be sucking up anomalous moisture from what was the Hurricane depicted in your first graphic. This could be getting into the potential area though, EPAC is upticking a lot.

    • AntiochWx

      I’m leaning with the Euro, it has a fairly strong ridge off shore. Usually to get any tropical system to get pulled into California, you need a fairly anomalous trough right where the HP is centered. https://uploads.disquscdn.com/images/7eb44e6b1545a9da4d490d5986907482c13b6e88d7ae767589d5eb81737e0aa5.png

  • AntiochWx

    Who wants to do some spell casting to increase our odds of getting a Terribly Tenacious Trough?

    • happ [Los Angeles]

      That includes GOA systems and Hawaiian express

      • 805 Weather (Camarillo)

        Down south this time please.

      • AntiochWx

        and ARk storms!!

    • Fairweathercactus

      Can you cast a love spell as well?

      • AntiochWx

        I will consult with the user manual.

        • Pfirman

          Strike the ‘with’. Sounds creepy.

  • Charlie B

    A lot of good discussion going on. This is what I call the summer boredom fueled discussion of the upcoming winter during the midst of the fire season when the state is generally burning and we all yearn for a change (or “sbfduwdmofswsigbwyfac” for short.) It is a hearty and well respected Weather West tradition, for those new here. Here is my take: During this upcoming fall, winter and spring there will be periods of rain in lower areas and snow in the higher mountains. The north state will likely receive more precipitation than the south. Heaviest precipitation will likely fall in places in the north coast mountains like Honeydew and in the lower northern Sierra like Rag Dump. Helen Lake on the south slope of Mt. Shasta will probably win the snowfall crown for the year.The deserts will generally be dry and mild. Certain areas such as Truckee, Alturas and Bodie and Bridgeport will experience cold snaps with temps slightly below zero for a few days. A prolonged arctic outbreak is unlikely but possible. As fall progresses it will generally get colder and wetter statewide, bottoming out in late January and gradually warming though the later winter and into the spring. The snow pack will peak around April 1 and gradually melt after that. The central valley, especially the San Joaquin, will experience dense fog on occasion, especially during times of high pressure aloft which result in strong inversions. In between storms, the coast will be delightful, and the skiing, especially at higher elevations, will be fine. The spring will see some nice convective thunderstorms, but none will be that strong (by mid west standards), and none will be destructive.

    • Tuolumne

      And the #1 generator of hot air will be seasonal weather prediction arguments on this site. 😉

    • Cap’n

      Hey Charlie, I think our predictions on what Central Sierra Snowlab on Donner Summit at 7K would end up with we’re right in the middle (they ended with 560″). They should pay us. Thanks for pointing out this page Al.

      https://uploads.disquscdn.com/images/2b39c99d9d99088073029f92e6ef56e395cd661beb010ee29be54dd98d0f71cd.png

    • Thunderstorm

      This reads exactly like the Farmers Almanac.

      • Charlie B

        Or a horoscope.

    • Jason Jackson Willamette

      Are you God?……

      • Charlie B

        No, but I did stay at a Holiday Inn Express last night.

        • Jason Jackson Willamette

          Ha! Good enough for me!

    • gray whale

      JUST BECAUSE THAT HAPPENED IN ’51-52 DOESN’T MEAN

      oh you’re probably right.

  • molbiol

    With all due respect, WRT monsoon surge this weekend: The GFS has done an absolutely horrific job and has zero accuracy more than 48hrs out for Socal. Ensemble spread (which I won’t show here since no one looks at that) is very large next week. I guess being at the junction between the subtropics, marine air, and monsoon air is too much for it. Also, it seems like its very hard to forecast the exact position of the anticyclone more than a couple days in advance. Not sure why this is though. …Now back to the global warming wildfire mass hysteria…

    • 805 Weather (Camarillo)

      Truly it has, as always just looking for consistency & trends.

  • happ [Los Angeles]
    • Fairweathercactus

      Stupid offshore flow.

  • happ [Los Angeles]
    • Jason Jackson Willamette

      Yep. Port Charlotte, FL I looked up the guys name in the photo. Port Charlotte is on the west coast of FL, between Ft. Myers and Tampa. Used to live there as a kid. Thunderstorm city!

  • 82/83 El Nino baby (San Jose)

    Saw this 207/18 Winter prediction by Southern California Weather Force. Hope they are right.

    http://www.southerncaliforniaweatherforce.com/2017/07/21/preliminary-2017-2018-storm-forecast-for-southern-california-shows-neutral-enso/

    • FYI…that is not a source of objective weather information (to say the least). The proprietor has seriously harassed many in the weather community on numerous occasions (myself included). Proceed with caution; the National Weather Service was at one point forced to send out a national bulletin disclaiming his activities:

      http://www.nws.noaa.gov/om/notification/pns11martin.txt

      • 82/83 El Nino baby (San Jose)

        Thanks for noting! With this the case, I will delete the content to avoid giving the guy ad revenue.

        • Someone else

          A while back he and a puppet account attempted to invade the blog, culminating in Weatherwest smiting all records of it from the page at the time. KM is a d***bag. Fortunately he has not returned since.

      • mattzweck

        i had to tell one of my friends from the other job i work at that it was not informative site. had to get him to look at your site Daniel .

        • molbiol

          Didn’t realize he was still around. He is notoriety extends to the east coast and he has even harassed the storm chaser community in the past

        • Jason Jackson Willamette

          whoa. Just read up on the guy and he’s certifiable. What people will do for attention…..

      • weathergeek100

        He is consistently harassing the NWS San Diego on their Facebook page over…and over and over again. So annoying.

  • 82/83 El Nino baby (San Jose)

    This graphic puts the size of the Detwiler fire in perspective.

    https://twitter.com/NWSBayArea/status/888479900365189120

    • Regional models actually yielding quite a bit of elevated convection from coastal SoCal up through the Sierra Nevada foothills. This would be very bad fire weather news.

      • Pfirman

        That’s cra. I heard it somewhere.

    • Just what we need!!!! Sarcasm.

    • “That’s cra” – from my daughter, not me.

    • Craig Matthews

      Was waiting for one of these while I was up in the redding area. sigh

  • Rainmaker (San Jose)

    wow, GFS 12z showing rain everywhere mon-tues for this monsoon surge, except for the bay area. Rain off of the coast, all over Norcal, all over the mountains, and all over Socal. But nothing for us bay area folks. We lose our treasured fog and get dragged in along with the heat with everyone else but nothing to pay for it. Sad!

    • 82/83 El Nino baby (San Jose)

      Now the rest of the Bay Are will feel how San Jose folks do most winters when everyone else seems to be in on the fun and we get to just watch from the sidelines.

  • SoCalWXwatcher

    I appreciate NOAA’s abundant caution, but is it really necessary for every GOES-16 image they put out to come with the “Non-operational” disclaimer? I’m sure they’re still calibrating things before it becomes operational in November, but it’s not like it’s going to depict a feature that isn’t there. It pretty much shows everything the older GOES satellites do, only much clearer.

    • Dan the Weatherman

      The animation on that new satellite is incredible! Since the images are taken much more frequently, the animation is very fluid as if you are watching a time-lapse video of cloud movement.

      I can’t wait until it becomes operational and we will be able to see every thunderstorm that develops over a given area such as Socal. I believe it will also be easier to see flow patterns especially if there are clouds moving in different directions at different altitudes.

      • SoCalWXwatcher

        Looking at thunderstorm buildups over the SouthWest over the past couple of weeks, I’ve never seen so many outflow boundaries from strong cells visible on satellite. That is a huge plus when assessing mesoscale weather features.

        • Pfirman

          I am wondering how many scales for weather. Meso…sure. Macro…..I guess. Nano…..maybe. Others?

      • SoCalWXwatcher

        The problem is, when it becomes operational it will be moved to the GOES East orbital slot. We have to wait for the launch of GOES S to get our own West Coast/East Pacific bird up there. 🙁

    • 805 Weather (Camarillo)

      Was wondering this the other night when the posts of photos were so frequent.

    • It hasn’t gone through final testing yet

      • SoCalWXwatcher

        I understand, but do we really need a disclaimer for a black & white 1km resolution picture of the CONUS? ¯_(?)_/¯

        • You and I do not but until it’s certified and gone through all of its testing….they won’t put the seal of approval. IMO it’s a waste of Twitter characters when tweeting though ?

    • Yanet Garcia (NYC, USA)

      I stamp this on many men after I date. I break things.

      • SoCalWXwatcher

        This hills are littered with broken hearts, casualties of Her-icane Yanet.

  • Thunderstorm

    Since Daniels track record is excellent. Next week looks bad for firefighters.

  • 805 Weather (Camarillo)

    That is one solid looking upper level low coming in to sit up off the north coast… Now the placement of each puzzle piece for Tuesday’s potential outbreak will need watching. https://uploads.disquscdn.com/images/4961f9518d548c95b87bc44a14f1c524c49bebf57c287772deb0ffa5d1073ea9.gif

    • molbiol

      The 18Z operational GFS is if nothing else..entertaining in the short mid and long term.

    • AntiochWx

      I’m not sold on the digging of the LP (not with the west coast ridge there). I understand why the GFS wants to bring the tropical system in towards California, but its mainly doing so because it thinks there will be a weakness between the HP off California and the 4 corners HP. I’m willing to bet the HP tilts enough to close the weakness and blocks any further movement and guides it out to sea. It could get close enough to draw in some moisture, but I think it be relegated to the southern most spots of California.

      • DelMarSD

        Probably way to early to tell either way.

        • AntiochWx

          It is, we still have a few days to get a better look. We are talking about HR 168-180, so its close. At the very least should get some cloud cover out of it, but SD area has the best chance out of anyone.

          • 805 Weather (Camarillo)

            I was talking about the event on Sunday-Tuesday when I posted this sorry, may have not been too clear on that.

          • AntiochWx

            No it was clear, I got confused, have been talking about multiple events on this page my thinking got jumbled.

          • 805 Weather (Camarillo)

            I am trying to keep up as well lol! Got thrown into a spin with all the discussions earlier.

          • Pfirman

            Cyclonic or anti-cyclonic?

          • 805 Weather (Camarillo)

            Cyclonic.

  • Cap’n

    Reno AFD:

    “By Monday, models continue to increase the moisture with PW
    increasing to 1 inch or more. The forcing also remains favorable
    so wetting rains are likely from the storms. Localized flash
    flooding is also possible if this much moisture is present (and
    there is enough solar heating).”

    • AntiochWx

      This is definitely the best monsoonal surge of the season so far.

      • Cap’n

        It’s about time! The dirt is so dry and dusty up here. I like the sound of “wetting rains” instead of dry lightning, although I guess that isn’t out of the question either.

    • 805 Weather (Camarillo)

      Good news if you ask me. Means the lower levels may be better impacted by the surge (less chances of dry lightning)

  • honzik
    • Thunderstorm

      Clouds from the upper low cutting off at 140W.

  • Jim
    • honzik

      Those are the same clouds as below, but from a different angle! Very cool!

  • happ [Los Angeles]

    Another monsoonal push starting Sunday; it hasn’t rained since May 7th
    88/ 66

    • Pfirman

      88 / 66, ????

      • happ [Los Angeles]

        Max/ min for the day

  • Craig Matthews

    Gorgeous skies over upper Carmel Valley-Cachagua this evening. Nice to be back home again. https://uploads.disquscdn.com/images/8a64201a4decc9bdf40e7228b5b36e44fc1c3252f224925bb8c51ed37ba86a03.jpg

    • alanstorm

      Welcome home!

      • Craig Matthews

        Yeah its good to be back here. Its in the upper 60’s here too. Starting to wonder about tomorrow’s heat myself, though in this particular area colder nights tend to be followed by hot temps the next day, due to drier airmass w/ northerly flow in place this time of year. Will see.

        • alanstorm

          Onshore flow would need to get going now for that to happen.
          No sign of it yet, still nice and cool out. Had to put on a sweater

          • Craig Matthews

            lol, yeah I had to dig out my long sleeves. Haven’t seen those in a while. Its down to 63 here now.

    • Craig Matthews
  • alanstorm

    A nice cool night here in Mendocino Co. Was only 88° today.
    Supposed to be 104° tomorrow.
    I just don’t see how that’s possible.
    It’s a mere 69° right now

    • Pfirman

      I have noticed the threatened highs have mercifully underperformed. Maybe the price of Viagra went up.
      As a stupid aside, my county webpage, Yolo, says the current situation, a little past nine thirty at night, is ninety degrees F and sunny.
      It is actually about eighty degrees F., and of course, dark. That said, it still was in the nineties today and promises to do so through next weekend, when it ‘threatens’ triple digits again.
      At least the mornings have been mostly cool.
      But I have had enough.
      I want the Delta breeze, not the Melta, at least one evening a week. Not too much to ask, at least historically.

      • alanstorm

        Haha Pfirman, as always.
        I wouldn’t know about the Viagra/Virga/Sophia Vergara

        • Pfirman

          Thou dost protest too much.

  • Thunderstorm

    NWS out of Portland – Weak low off northern california coast monday forecast to track inland farther south, already water vapor imagery showing development of low. Expect limited moisture with high based storms and fire weather concerns.

    • Is the low SW of Cali on the map?

      • alanstorm

        I was repeating the Eureka NWS discussion

    • alanstorm

      Upper level low supposed to come ashore Sunday “south of Cape Mendocino”.
      That would be me.
      Please no dry lightning!!!!

  • DelMarSD

    SD NWS:

    “There is a slight chance of thunderstorms over the coastal waters
    Sunday night and Monday as an upper level disturbance moves through
    the region. ”

    Hoping it happens!

  • 805 Weather (Camarillo)

    “Area forecast discussion National Weather Service Los Angeles/Oxnard California 845 PM PDT Fri Jul 21 2017

    Monsoonal moisture is forecast to start moving into eastern parts of the forecast area late sun and Sun night then push further W over vtu and sba County thru Mon. The 00z NAM forecasts slight instability, but a decent amount of moisture with precipitable water values near 1.6 inches along the l.A. County coast, and 850 mb dewpoints in the 5-10 deg c range. There will be a slight chance of thunderstorms for the mtns and deserts on Mon, but there are indications there could be some showers and perhaps an isolated thunderstorm for parts of the coast and vlys on Mon, especially for vtu/l.A. Counties. This situation will have to be closely monitored as the models have not been in great agreement on the extent of monsoonal moisture over the region during the last few runs.”

    • Craig Matthews

      That sounds nice to have the 850mb moisten up like that down in that area. With some upper level support, convection could go crazy, with the cloud bases a little lower over the mtns then usual. Good for gully washers in the Mt Pinos district and elsewhere in socal mtns and perhaps valleys?. Up here in nor-central ca, I think its gonna be a 700mb+ type deal irt moisture and convection….there’s just too much dry air in the lower levels to overcome even if decent advection occurs IMO. But sierra could generate some lower level moisture-lower cloud bases

      • 805 Weather (Camarillo)
        • Craig Matthews

          Wow that’s some insane vort-lobe action around that Upper level Low. Looks especially interesting where the monsoon flow meets the Upper Level Low’s cyclonic flow field over central ca, and where these flows come together over the central coast. Even with a ssw flow over central ca, having 2 airmasses meet where the different flow patterns meet could spark a few ssw-nne lines of elevated convection across central ca. Wish that upper level low would locate due west of Pt Conception to pull moisture further west over central ca, also placing central ca in the NE quad … deep veering sse to ese flow in the mid levels..notorious for generating elevated convection. But right now looks like that will be over Norcal per latest runs. Also interesting is the fact the Low has a relatively colder center w/ slightly below ave heights at 500mb. This brings steeper laps rates with the stronger vort-lobes compared to the upper Level Lows we’ve been seeing the summer so far which have carried borderline upper level support/lapse rates.

          • 805 Weather (Camarillo)

            I believe that the two lows may get a chance to mingle actually down the road, we’ll see. GFS is having a hard time lol. NAM & Euro are the feisty ones with the two different outputs.

          • Craig Matthews

            Goes to show that in this particular set-up and in the process of unfolding events at this time, more emphasis should be placed on the use of satellite/satellite animation interpretation and surface obs then model outputs(though model outputs are important to observe and interpret as well, esp. irt synoptic scale). As we’ve seen recently, just one MCV and associated outflow boundaries can create real havoc in the forecasts as disturbances pop outta nowhere from those Mesoscale features…..like the ones that keep popping outta southern AZ and affecting socal.

          • 805 Weather (Camarillo)

            I completely agree, & an example is what is beginning to occur in AZ this evening.

  • Rainmaker (San Jose)

    Its getting closer! 12z had it aimed in off of Socal, now it is progressing further north on the 0zz. My dreams are slowly coming to fruition
    https://uploads.disquscdn.com/images/47b55ceb437374e77a90e90d443a6ba4057c0e3e4a0a81176de68ac854ece11c.png

  • Great Winter of 2017 (SMC)

    Looks like I will be seeing thunderstorms here in Ashland and Medford Oregon. Surprised monsoonal moisture can make it this far North.

    “Saturday night into Sunday evening, the aforementioned upper low will

    be lurking off the Northern California coast. The upper low will tap

    into some monsoonal moisture with the upper flow becoming southeast

    and this in combination with increasing instability and hotter

    temperatures will bring an increased risk for thunderstorms Sunday

    afternoon through Sunday evening. Right now, we think the storms

    will first develop over the Cascades, Siskiyous and portions of the

    eastside, then expand in coverage by Sunday evening. Since the 700mb

    flow is expected to be easterly and 700-500mb flow southeast, there

    is a chance that any storms that form over the Cascades and

    Siskiyous could drift into portions of the westside, including the

    Rogue, Illinois, Applegate and eastern Douglas County. Right now we

    have a slight chance for these areas, but the details on this could

    change, so watch for updates on this. Of note, the models show

    greater instability in the northern Cascades so we have a chance for

    thunderstorms there.”

    • Rainmaker (San Jose)

      excellent use of MLA format

  • 805 Weather (Camarillo)

    Great AFD giving the idea of the variablity within the GFS & why they use caution on bringing up the chances for thunderstorms from NWS LA/OX this morning. It seems like the bigger wildcard looking at the models as of this morning is how they wave will make it passed the transverse ranges & the eastern Sierra’s…

    “Area forecast discussion National Weather Service Los Angeles/Oxnard California 333 am PDT Sat Jul 22 2017

    Monday’s forecast really depends on what mdl is right. The GFS has quite the bullish monsoon forecast. It pushes precipitable water values as high as 1.4 inches vta and sba counties. Li’s lower to -1 or -2. The only question with the GFS forecast is how much mid and high level clouds will arrive with the moisture… there is a chance that the day could be mostly cloudy which would inhibit the convection. Still if the GFS is perfect… there will be a great deal of convection in the afternoon and evening across the mtns and the av as will as the Santa Clarita and San Gabriel vlys.

    But… the ec keeps all the moisture to the S and east of the area. The GFS has been over forecasting the monsoon front fairly relentlessly over the past three weeks and tend to favor the drier ec at this time. Still cannot ignore the GFS (hey its gotta be right sometime) and have slight chc pops in the fcst for now. Will have to monitor this and see which mdl trends to the other.”

    IMHO I think due to the high-based nature of the convection we have been seeing this summer, the airmass shouldn’t stop at the mountains, but chances of that marine layer once again disrupting the lower level flow & further destabilizing it could be the biggest fly in the ointment since the southern low coming in will indeed aid in keeping the marine layer nearby as the setup continues to evolve.

    • 805 Weather (Camarillo)

      Another factor that will likely change run-to-run consistency is MCV activity associated with the wave. As has been noted here before, even just one mesoconvective vortex has the potential to change a short term forecast (6 hours out) for any location within it’s vicinity like we have seen a couple times with the vortexes that have been moving across Vegas. So this wave will certainly need watching. From my standpoint it looks like this will be the strongest surge we’ve seen so far this season. Here is the latest NAM infrared showing the storms blowing up & then residual energy moving far enough west later in the run. https://uploads.disquscdn.com/images/5bc54e50d441c3fc09b6a744c5abb064912f817fcf0a01498b5fa339dbc7e46c.gif

      • Craig Matthews

        I think this is a very cool visual representation of how large thunderstorm complexes reaching toward the upper troposphere-tropopause reveal 2 different eddy flows within the entire system there over the desert sw: the upper level anti-cyclonic circulation associated with the upper level desert sw High, and the mid-lower level cyclonic flow associated with a mid level Low underneath and just slightly west of that upper level High axis position. In a very strange way this almost seams like something we’d see with a Hurricane irt upper level and lower level flow patterns in places like the MDR of the Atlantic. Sure is interesting, wondering if you are seeing what I am talking about? I could be wrong about what I am seeing though…..

        • 805 Weather (Camarillo)

          I look for trends in these infrared graphics, it’s incredibly useful for vorticity!

          • Craig Matthews

            Can I get access to those images?

    • Craig Matthews

      Going off persistence of the monsoonal pattern as of late, I’d say EC is more in line with reality for central and norcal. However down in your area I think you could still be in on some action. But what do I know, lol. This may totally pound us anyway.

      • 805 Weather (Camarillo)

        NAM sure does think so on Monday…

  • alanstorm

    Well, 50° at 6:30 am for Willits. No sign of that warm offshore flow yet!
    I see the 104° for Ukiah today is still hoisted.
    I’m betting 99° tops

    • Craig Matthews

      Seams like they are way off on this one. Last night was much colder here, marine layer is 10 miles further inland then yesterday. I’m 26 inland, but feeling the effects of the marine air, whereas yesterday not so

  • Craig Matthews

    Low of 44 in Cachagua, and 45.5F now at almost 8am. Suppose to be 10-15 degrees warmer today with a compressed marine layer below 1000ft according to yesterday’s and last nights San Francisco AFD. As I was driving into town just now (into the Carmel Valley Village) was surprised when i got over the grade to see a thick marine layer on the other side. Then as I dropped down into that thick marine layer there was drizzle, enough to wet the roads. Marine layer depth was at 1200ft, and marine inversion layer above the marine layer is at 1500ft. Starting to wonder if NWS is off on this warming trend for this weekend in the coastal valleys… Yesterday there was no marine layer up the valley like this and temps were already in the upper 60’s. https://uploads.disquscdn.com/images/eea5b21eb34ac7015990dc69f44b719c945eef0b2315975740951bd68a906d9a.jpg https://uploads.disquscdn.com/images/a5deb53786ff2d64007f466f27d4f70b8f4985fe693a38ba491fd4f5a9ba2ce3.jpg

  • Great Winter of 2017 (SMC)

    Long time since we since this in the mountains

    “Low pressure remains along the northern California coast on Tuesday, bringing a vortmax through northern California/Nevada on Tuesday afternoon. This wave will expand thunderstorm coverage and even bring some organization to the thunderstorms as the exit region of the jet moves overhead. We have increased chances for thunderstorms on Tuesday with threats of small hail, gusty winds, and localized heavy rainfall. Thunderstorms will be on the wet side, with precipitable water approaching one inch. Flash flooding could be a possibility especially on recently burned areas.”

  • Craig Matthews

    At this time, 854am, its 93 in Redding with a downslope North wind along with very low RH in teens, with some RAWS reporting single digits this hour. While at the same time, temps are in the low 50’s in upper Carmel Valley with no wind and high RH. I know I’m repeating myself but can’t help it. Just feels so nice to breath the fresh, cool, moist air again.

    • 805 Weather (Camarillo)

      Interesting.

      Area forecast discussion
      National Weather Service San Francisco Bay area
      807 am PDT Sat Jul 22 2017

      Discussion…as of 08:07 am PDT Saturday…clouds developed
      overnight along the coast and continue to impact areas from Point
      Reyes south along the central coast. The Fort Ord profiler
      indicates the marine layer has increased a bit within the past
      several hours to around 1,200 ft. San Francisco Bay area airports
      have managed to stay mostly clear this morning while Monterey and
      Salinas continue to be plagued with overcast conditions with
      ceilings around 500 ft. Temperatures at the major airports are
      within a few degrees from what they were at 24 hours ago, but
      there are noteworthy changes in the hills where many locations are
      running about 4 to 8 degrees warmer. Additionally, the 12z
      Oakland sounding shows warming at 850 mb — today it is 22.0 deg c
      whereas yesterday it was 20.4 deg c. This will translate to 5 to
      10 deg f warming at the surface for many interior areas with the
      hottest locations surpassing the century mark.

      No major changed planned for the forecast this morning. For
      additional details, please refer to the previous discussion.

      • Craig Matthews

        Marine layer was suppose to compress below 1000ft so this was an unforeseen surprise. Marine layer depth is very hard to predict. I’ve noticed that this is a struggle as I have read through the local AFDs over the years….. being there are so many factors at play that influence the depth of the marine layer, and in localized regions like what we are seeing this morning. But with the warming above the layer, inland areas will see the warming as predicted, and areas in the Bay Area will also see that warming. AFD was mentioning a southerly surge could also ensue at some point later this weekend as well. So now, it looks possible that areas south of Half Moon Bay and immediate coastal areas and some lower coastal valleys of Monterey Co may actually cool this weekend instead of warming, being the stronger marine inversion plus heating over the interior Bay area and inland areas may keep immediate coastal areas of Monterey socked in compared to the last several days.

        • 805 Weather (Camarillo)

          It’s always tricky down here for NWS LOX as well. This time my guess is it may be due to the southern low coming up from the south.

          • Craig Matthews

            Yeah think you’re right. I notice the northern Low’s position according to forecast will also draw in a stronger onshore push over the central coast, with a slight southerly component to the flow out over the waters, starting tomorrow and thru about tuesday. But am sure much more interested in the convective potential as you are too.

    • alanstorm

      Anything with the name “Red” in it is impossibly hot.
      Redding
      Red bluff
      Redlands

      • Craig Matthews

        Hahaaa. That’s just too many “reds” for me, lol.

      • Tuolumne

        Red Mountain (5,261′) in the Mojave Desert is also pretty hot in summer.

        But not these spots in the Sierra Nevada:

        -Red Mountain in Nevada (7,841′), Fresno (11,969′), and Mono (11,472′) counties.
        -Red Lake and nearby Red Lake Peak in Alpine County.
        -Red Lake (~9,000′) in the Fresno County high country.

        Nor Red Banks up near the top of Mt. Shasta.

        Have some more ‘reds’, Craig!

        • Craig Matthews

          I’ll take em’ lol. I passed by Red Mtn in Sierra but can’t remember if that was near Mineral King or around Kings Canyon area?

        • Pfirman

          At one of those last is near Mcgee Pass if I reckon right.

  • Fairweathercactus

    The 12z GFS was gone the way of the much more dry Euro.

    • happ [Los Angeles]

      At least the monsoon is in full force in Arizona/ New Mexico so chances of rainfall are always possible for coastal SoCal.

      • annette johnson

        If it could just get passed “the wall” which is the Colorado River. For the last couple weeks some really great moisture has stopped just 15 miles east of us. Really hoping what Craig posted above verifies.

        • happ [Los Angeles]

          Las Vegas was stormy this week

          • annette johnson

            True. Vegas usually sees a little more action than we do lol.

    • AntiochWx

      King Euro

  • happ [Los Angeles]

    I would love to see some moisture west of mountains. The idea of cloudy/ cooler/ possible convection late Sunday going into Monday/ Tuesday sounds heavenly. July has been humid but essentially rainless outside desert areas. Temps above normal but not horrible heat this month aside from 7/7-11. Positive departure minimums.

  • alanstorm

    Ok. 86° & rising quick. Feels way hotter. Why? 41% humidity

    • Craig Matthews

      That’s a jump! Getting a good onshore breeze down here which is keeping temps cooler then yesterday at this time, so far. Temps in mid Carmel Valley are now upper 60’s. Marine Layer is looking thick to my west.

    • Yolo Hoe

      96F in far southwest Davis with 32% humidity at 1323 — agree it’s a bit muggy — will be roasting in a couple hours when we hit triple digits

  • Craig Matthews

    Couldn’t resist posting this one b/c of it’s anomaly potential and how good it looks. Talk about a lot of moisture, wow! Sure wish something like this would happen in the real world. This is 216hrs away, sigh. https://uploads.disquscdn.com/images/4125ad664b5c3b69959b2246777d0d99aaa6724001079cdf90b17bcc832ece10.png

    • 805 Weather (Camarillo)

      This is the product of the scenario I was talking about with the upper low off the coast. Who knows though? Lol Euro coming in.

      • Craig Matthews

        Yes that was a very interesting post about that Low. And hopefully it remains. I noticed the Euro last night was showing a more favorable ridge position placing us in a deeper southerly-se flow at the 216hr. And if that Low you are talking about remains we could be in for some real interesting times. So will see what it does next. I hope this one pans out.

        • molbiol

          I have a bridge I think you might be interested in buying…
          😉

          • Jason Jackson Willamette

            Let me paint it first for ya. Then I’ll take a 20% cut of the sales proceeds…

          • molbiol

            Agreed but you must buy your own paint and it must be high quality. 20% seems a little high..15% sound better?

          • Craig Matthews

            Here ya go.. one of my projects from last week, lol…Built in 108 degree wx ugh fortunately only took a few hours in the morn. https://uploads.disquscdn.com/images/a2a432c478b294adb17ec85c846444fc5fb562726cdcfa6b7483a8bed1b976b4.jpg

          • TheNothing

            Are those pine needles blowing in the wind or did you accidently superimpose this picture on another?

          • Craig Matthews

            There is netting surrounding the north end of that small pond that goes underneath the bridge to keep various fish from getting snatched by birds while the fish are being fed.. With all the grey pines in the area, a lot of pine needles tend to collect in the netting. So I guess that made for a strange look hah. . Here’s another view, bridge is still not finished just yet. No superimposing here… just a simple bridge for the owners. https://uploads.disquscdn.com/images/c8298116c5e048c6517479c5e68c578e65aed245bf06c9a1d1a614bdade080ad.jpg

          • Jason Jackson Willamette

            Solid Craig! Redwood? What kind of finish did you put on it? Looks like Flood CWF-UV finish.

    • Thunder98

      The Pineapple Express is paying a visit?

    • jstrahl

      Nice to see, though most likely just a tease.

  • Stefan Myslicki

    In an unrelated question..anybody know what the heck is the fidget spinner symbol in this weather map?http://www.wpc.ncep.noaa.gov/metwatch/metwatch_mpd_multi.php?md=0534&yr=2017

    • molbiol

      That appears to be the intersection of several outflow boundaries which has resulted in a vorticity maximum or in this case an MCV. Note the orange dashed line which intersects the stationary boundary. This is north of the warm front

  • SoCal Al (El Monte-SGV)

    Keeping my fingers crossed for at least “sprinkles” and cooler, though humid weather Monday and Tuesday. Been in the low-mid 90’s for the last two weeks, so hoping for a temporary break.

    From Oxnard:

    Model solutions are pointing toward a decent monsoonal surge on Monday and Monday night. GFS and NAM-WRF solutions keep this idea in mind and early frames of the NCEP high-resolution WRF NMM and ARW core solutions are hinting at a similar solution. PoPs will likely be increased over the area, possibly spilling over showers and thunderstorm activity into coastal and valley areas for Monday and Monday night. Precipitable water values in NAM-WRF and GFS solutions increase to 1.50-2.00 inches. 850-700 mb mixing ratios and dewpoint are impressive ranging up 8-10 g/kg and near 10 degrees Celsius. A warm, cloudy and humid air mass should expected for Monday and Monday with the possibility of at least embedded sprinkles at times.

    • Fairweathercactus

      Anywhere els in the US that would lead to explosive thunderstorms lol.

  • Yolo Hoe
    • Beth_ElDoradoHills

      How terrifying – this seems much earlier than usual

      • Pfirman

        Odd response. It all looks perfectly normal and healthy to me. For instance, you can find sunflowers being harvested as well as find them planted recently, so you can relax.
        Crop age is hardly uniform across the valley.

        • Yolo Hoe

          Yep, timing is well staggered to accommodate harvesting and processing — saw first tomato trucks rolling today while in many fields the fruit is still all green — same with the sunflowers as you note.

        • Beth_ElDoradoHills

          The early plantings should be ringing off warning alarm bells in youre head.

          • Pfirman

            They were not that early. We had a pretty wet and prolonged spring. Do you remember?

    • Jason Jackson Willamette

      Those sunflowers are amazing, heavy with seeds. I’ve discovered putting them on my evening salad, hulled of course. I get the roasted-salted ones from the bulk bins at Sprouts. Really gives the greens a wonderful taste and adds protein and fiber to the meal. Mmmmmm, can’t wait for dinner.

    • Pfirman

      Pretty good loop you rode. Nice shots, and not an almond tree to be seen, heh.

  • inclinejj

    85.6 Pacifica 2:27 pm so far the high for the day. 36 percent humidity.

    My Rain Gauge is showing rain again. Geo, is yours doing the same thing?

  • Thunder98
    • jstrahl

      Unlikely, but one never knows.

      • Thunder98

        I hope it happens this time

  • Henry

    Today is a continuation of the pattern we have experienced for much of late June and July of this year – a hot day that turns out to be even hotter than expected. 94 degrees at Los Gatos RAWS at 1800 feet, with parts of the south bay approaching 100. It is the third consecutive weekend with temperatures well over 90, that is something I don’t think we have seen in a while. Next weekend might make it 4 in a row.

    • Jason Jackson Willamette

      Officially 92 at SJC right now, 4:20PM. A hot day by the bay. Supposed to cool off some early next week.

    • 101 in south San Jose right now.

    • Dan weather maniac (ORINDA)

      Copy that it’s scorching in orinda around 100 earlier, now the seabreeze has kicked in and dropped it to 90 and falling fast. But ya it’s been hot.

  • Thunderstorm

    The biggest difference this summer here SF bay area by Fremont is no morning fog and hazy mornings from stubborn inversion layers.

    • 82/83 El Nino baby (San Jose)

      Agreed. I remember 10 years ago, normal summer days started with a marine later that burned off around 930. It never happens these days..

      • jstrahl

        There were several days earlier this month during which the sun hardly came out at all. At least in Berkeley.

      • AntiochWx

        I wonder if this is AGW related, or just long term variations.

    • inclinejj

      The fog is right off the coast.

    • When was the last time we had a marine layer besides the Bay? It has been a while.

  • Fairweathercactus

    POP 30% for Whittier hills. What I have seen today from the models I would hold off or take storms out all together. https://uploads.disquscdn.com/images/3a2733d362e022ea48af661ff0af16f3a608c8a20e917c9c983adbb1512b7f9a.jpg

  • Thunder98
    • Pfirman

      The fence sees all.

  • Thunderstorm

    Alto cumulus just starting to appear around the SF bay area.

  • Dan weather maniac (ORINDA)

    A little mid level action streaming up into the east bay hills……… about as good as it gets in the summer other than the usual marine influence.. haha…

    Maybe some action this week but I doubt it. I’ve lived her 16 years and never seen a summer thunderstorm. https://uploads.disquscdn.com/images/3d2168187215bdd49f683325830b9b5b92beb4faa33377cd68b08b1f1695167c.jpg

    Edit: I have seen lighting (in concord, more east than orinda, and sprinkles…. but never a proper downpour or thunderstorm.

    At least in Italy, the true Mediterranean climate, they can get some summer action with thier daily wine and fish delights!

    • jstrahl

      2003 is the last time i have a record of a summertime thunderstorm in the Berkeley area.

      • Thunder98

        2015 is the last time that Santa Maria has seen a Summertime Thunderstorm

        • Who Killed Kenny Strawn?

          2015 saw multiple summer thunderstorms in Orange County, a few in the summer of 2014 and one in San Jose (the week that I was up there and the locals said it was their first summer thunderstorm in many years). In 2016, no summer thunderstorms in OC at the coast but we did get some warm rain showers later in summer from remnants of a hurricane.

          • Dan the Weatherman

            There were thunderstorms here in Orange on at least 3 occasions I can remember during the summer of 2015.

        • thebigweasel

          I drove right through one at Santa Maria in August of last year.

  • John

    Time for more alternative weather facts. . . .

    I have been commenting on how much the NWS and especially WU under-predict high temperatures these days, for reasons no one seems to be able to explain. For instance, the high here in Orinda was supposed to be about 88 degrees; it was 99 per WU.

    Tomorrow, NWS predicts a range of 83-88 for my microclimate. In a breezy comment, WU tells me tomorrow will be MUCH COOLER than today; in fact, it will only get to 78 degrees.

    Stay tuned, I figure from the lack of movement outside at 5:30 pm, we will see 95 degrees. And my back yard, which faces west on a hill, was about 110 today and likely will easily break triple digits again.

    • Dan weather maniac (ORINDA)

      Hey John, agreed!scorching here near the theater. See my comments below.

    • I’m curious how you know that the NWS forecast and WU observation are both for the exact same microclimate. Generally, neither the NWS forecast or WU interpolated temperature has sufficient spatial resolution to be directly comparable, and in the Bay Area that is indeed enough to account for a 10 degree difference given the huge variations that take place over just a mile or two in this part of the world.

      • Dan weather maniac (ORINDA)

        I can vouch for what he is saying in downtown orinda. This has been the case consistently past 2 years. It’s much hotter here than advertised!

        • But exactly who is “advertising,” and how geographically precise does the forecast actually claim to be? That’s the key. There are quite a few locations in the Bay Area that are nearly always above or below the “forecast” for the broader “gridbox,” but more accurate numbers are impossible unless someone provides sufficiently high-resolution forecasts for regions within these geographically diverse boxes (which, as far as I know, no one does).

          tl;dr: it might be comparing apples to oranges.

          • John

            For WU, I put the location about 3 blocks away, with their station locator. I can say from experience (like, walking my dog out my door and past the WU weather station), that there is no functional difference between where I live and the WU personal station. If you have better advice than to find the closest, most similar personal WU station that you can, I’m all ears.

            For NWS, I drew the tightest user defined area forecast I could on their site. This is the link that allows one to put a tight box around where the forecast will focus:

            http://www.nws.noaa.gov/wtf/udaf/area/

            Again, I don’t know how it can get more precise than that. And anyway, c’mon! It’s not like I’m looking at Concord instead of Berkeley. I have a little more sense than that.

          • But what is the “WU” weather station, precisely? Many times, these are simply people’s backyard thermometers that can easily have 5-10 F error during the warmest part of the day.

          • AntiochWx

            but if they have davis weather machines, I highly doubt they have that large of an error. They all have shielding. Davis weather machines are darn near as accurate as NWS instruments.

          • It’s not the hardware that’s a problem, though (and higher end Davis ones can indeed comparable to official station). The big question, though, is how they’re sited: even a Davis/AWOS-grade station can give temperatures 5-10 degrees too high if not optimally located. The test you referenced is pretty compelling, but that was under absolutely ideal conditions (no pavement, no buildings, trees, free of obstructions, etc.).

          • AntiochWx

            Even the lower davis models like the vue, have been tested to be around -+1.5F. When I was at penn st, they also did some case studies year round of different local site settings. I wish I would have saved it, but they even found that if the machine was placed at least 5ft away from cement/asphalt in a suburban environment, even the vantage vue model was no more than 1.5F difference. Now if they were placed on a roof, near an ac unit, or within 5 feet of concret, I’d agree about the 5-10F, but I’d say most of the people who order a davis is going to be smart enough to pick a decent site. There are a lot of davis weather machines online recording daily data, enough to really quality control nws predictions. http://www.weatherlink.com/map.php

          • Great Winter of 2017 (SMC)

            I have my Vantage Vuw 5-6 feet above my deck, is this a good placement? Maybe somebody else could give me an answer

          • AntiochWx

            Do you have a grassy yard surface? Daniel might tell you something different which is fine, but my experience with penn st case study and my own experience, if its 5 feet away from concrete it will be ok, but obviously the further the better. Also 5-6 feet off the ground. Just don’t put it on or near your house.

          • The surface of the deck will probably affect the temperature to a modest degree–perhaps a few degrees F. It’s better than concrete, but not as good as an irrigated lawn (which is considered “ideal”). It also depends on how close it is to vertical obstructions and buildings…

          • AntiochWx

            yeah I’d get it on the grass if possible.

          • Great Winter of 2017 (SMC)

            Ya I do but 30 feet below in my backyard, my rainfall would decrease by several inches at least and the vantage Vue is 10 feet away from my house

          • AntiochWx
          • John

            Two other points. First, even if the WU personal stations are running on back yard thermometers (that would be far-fetched in my mind), what of the NWS predictions I mentioned. They are off, as well. Also, I’m looking at readings off the same sites as the predictions. For example, that personal station at WU; or the user defined area at NWS. I’m not saying my readings are at odds; theirs are internally inconsistent.

          • After taking a closer look at the topography around Orinda and what the code on the NWS custom forecast page is actually doing, it’s not too surprising that there seems to be a mismatch between the forecasts and observations in that particular location. Orinda is smack dab in the middle of the strongest horizontal (west to east) climatological temperature gradient in the Bay Area (between Oakland and Concord, for example), and is also in the midst of some significant topography (the Oakland Hills, which get up to >1500 feet or so).

            Two issues are: 1) the exact degree of marine influence on any given day in Orinda is likely to be extremely hard to foresee in advance, as errors of 1-2 miles with the seabreeze front could easily lead to 10-15 degree temperature errors, and 2) the NWS webpage you posted does too much spatial interpolation–it’s averaging temperatures from the top of the nearby hills (cooler) with that in the valleys below (hotter). Thus, since Orinda is not on the top of a hill, I’d expect the numbers spit out by the algorithim on that page to be biased on the low (cool) side for Orinda. If you reached out to the Monterey NWS office on a quiet day, I expect you might get some more in-depth insights.

            It’s worth noting that this “low temperature forecast bias” problem is not happening everywhere in the Bay Area–which argues for a local mismatch between coarse forecasts, local topography & microclimates.

            Also: see the below comment re: poor siting of Wunderground stations, even if they’re of high hardware quality.

          • AntiochWx

            I’d argue the NWS is low temperature forecast bias for the Antioch area as well. We are nearly 2-4Fconsistently higher than predicted temperatures.

          • Interesting. There I’d imagine that the microclimate of the Carquinez Strait and afternoon Delta breeze might be hard to capture. It’s worth noting that the NWS doesn’t use microclimate statistical adjustments (as Wunderground does), which may account for the sometimes better Wunderground numbers (as they take the raw NWS temps and leverage their much denser obs network to develop long-term relationships).

          • AntiochWx

            Don’t get me wrong, I think the NWS does a great job, it just seems sometimes they are a little conservative with their temperatures. It is difficult with our delta breeze, some days it will be there from morning to night, others not so much. I think you will appreciate the davis weather link, it shows a nicely dense obs for the bay area. Granted yes, some are not accurate, like the one near me I question there site location, but many near me are dead on.

          • AntiochWx

            Today was a good example. Forecast high was 100F, hit 104F. Today actually had a fairly impressive diurnal temperature variation, had a low of 57F for a diurnal range of 47F!

          • Dan weather maniac (ORINDA)

            Very interesting and appreciated analysis, and I know that must be true because my porch thermometer in the shade can’t be that off…and it is way hotter than advertised here!

            That and just from observation the fog often stalls over the Oakland hill side of orinda while the hot air from the Diablo valley pushes upward/west toward the same fog/Oakland hill.

            I’ve posted many pictures of the fog spilling over the hills in the am but stopping/clearing right in downtown orinda.

            On a hot inland day like today with low marine influence, the warm air from the diablo valley (concord/Walnut Creek ) must push up /west/ expand toward the Oakland hills… and orinda being where it is gets scorched!

          • John

            Dan:

            Thanks for the corroboration. And here is round 2. Yesterday, NWS predicted a high between 83-88; today it’s upgraded to 85-90. And WU is stalled on a predicted high of 81 (LOL). As of 7:30 am, it’s 68 degrees here, a slight breeze. I’m predicting more like 94 myself.

            Dr. Swain: the analysis is much appreciated, and that goes a good way to explaining the errors to the low side. But the funny thing is that the models are predicting for their very site, and still underpredicting. Plus, NWS predicts a range, which I thought accounted for temperatures at slightly different elevations. For instance, 85-90 today seems like more than one would estimate for one location.

            Anyway, as said, thanks for responding. This is a minor irritation compared to wondering how much more my back yard will slide this winter!

        • AntiochWx

          I sometimes wish NWS would just forecast in 5 degree ranges. Say todays forecast in Orinda is 86-91. I think it would help in viewer statisfaction. Then we can just laugh when the temperature actually still misses the range.

    • mdpatguy

      John is spot on about WU severely under predicting high temperatures this season. I have had a WU station in the Lafayette hills for several seasons now and this summer the WU high projections are consistently about 10 degrees too low. Tomorrow it says a high of 87 but it will end up being more like 97. The error was never this large in past seasons (same station, same location). WU needs an upgrade to its learning algorithm for the East Bay hills.

  • Great Winter of 2017 (SMC)
    • Dan weather maniac (ORINDA)

      Was 1974 winter good for Ca?

      • AntiochWx

        La Nina year, I also generally don’t like using 70s analogs due to that cooler time period.

        • HighWater

          For sure. Much much colder climate back in the 70’s i remember it all to well

      • Great Winter of 2017 (SMC)

        Nope below

        • Fairweathercactus

          73-74 near average. Only below by less half an inch. same with 74-75. After that it was stink bomb city.

      • jstrahl

        Are you talking about the Winter part of ’73-4 or of ’74-5? Winter ’74 on its face would mean the former, i.e. Jan-March ’74. March was WAY wet in the Bay Area, season as a whole was way wet, almost as much as the El Nino season which preceded it. ’74-5 started dry but finished a bit above average, really wet Feb-March.

  • Who Killed Kenny Strawn?

    Will soon to be hurricane Hilary bring us some remnants in about 10 days?
    https://www.tropicaltidbits.com/storminfo/09E_gefs_latest.png

  • Chris

    Love the microclimates of the Bay Area.
    Driving south on 101 from San Jose, it was 98 degrees in the Coyote Valley.
    Between Cochrane and E Dunne, I passed the northward moving sea breeze front.
    Temperature dropped from 98 to 93 in less than a quarter mile.

  • Taz & Storm Master

    sunday too tue will be big test days for the Detwiler Fire if we get a dry t-storm outbreak even no its now up too 30-Percent Containment they can lose that 30 Percent Containment at any time i seen that happen many times

  • Dan weather maniac (ORINDA)
  • 805 Weather (Camarillo)
  • AntiochWx
    • Beth_ElDoradoHills

      would be interesting if someone studied this map to see if the green colors also represent tree trunks – the orange areas are known to be devoid of trees (deserts)

  • AntiochWx

    http://ggweather.com/enso/oni.htm

    Figured you guys might like this site.

    • Craig Matthews

      Jan Null’s sites are all so very interesting an useful. He also has animations for various el ninos of the past and a comparison animation between various el ninos, like for instance 1982-83 and 1997-98. Don’t have the time right now but I will send a link when I getta chance…well maybe you already have it but ill send anyway. He has tropical OLR anomaly data and OLR comparisons for past el nino and la nina events as well. Maybe you seen those too? I

      • AntiochWx

        His work is great, enjoy the site very much. Please do, post whatever link you think will contribute to this site, even if I do have it, others may not and will enjoy them.

  • Craig Matthews

    High today in Cachagua reached 101F at 3pm after an overnight Low of 44.5F. This type of temp range is more typical in September thru October here. Marine layer actually deepened very early this morning to around 1200ft to 1500ft along the Monterey coastline, but then compressed to around 1000ft this afternoon, which allowed temps just inland from the coast in this area to rapidly climb between noon and 3pm. Kinda the opposite of what typically occurs in this area with regard to diurnal marine inversion level fluctuation. Not much of a sea breeze this evening so far. But if a southerly flow begins up the coast overnight I suspect an influx of marine air up the valley where I live by morning.

    • Pfirman

      And here I thought you were so lucky not to have triple digit heat like here in the lower Sac Valley. I guess it’s everywhere.

      • Yolo Hoe

        Far southwest Davis hit 105F at 1656 this afternoon — currently 81F at freaking 2221.

  • Fairweathercactus

    Here is a fun game to play. Try finding the last time downtown LA had a low of below 50 in May.

    • Beth_ElDoradoHills

      Lo s Angeles has a tropical climate so this is not necessarily possible for occurence

      • AntiochWx

        Oh but it is possible! Just go to show you how much warming we have experienced.

        • Beth_ElDoradoHills

          It is not necessarily possible

        • Shecky

          The average low for the last 100 years has been 58. 1922 was the lowest recorded in those years …we’ve had snow and hail in July while fishing at Bridgeport in the last 5 years. Freak things happen, but having a low well below the mean average in LA in May…you’ll notice it hasn’t happened but once in 100 years. You have a Mediterranean climate at best, next to a desert climate….May isn’t going to give you lows like that but once in a freak occurrence.

    • AntiochWx

      I’m going to guess 1922, but surely we must have seen one sooner than that.

    • AntiochWx

      Well I know it wasn’t anytime after 2000. Next guess would be 1976, but I have no idea.

    • AntiochWx

      What’s the answer?

  • 805 Weather (Camarillo)

    Enjoying the loops this morning as these three disturbances try to converge. A lot of motion at different levels today, & it will be really interesting to see how NWS plays the next two days. Waiting for the new runs to initialize. As you can see in the graphic, the northern low is starting to deepen. The big issue I am finding is whether or not the low to the south can pull the moisture/instability far enough west to make it to the coast, but the low coming in to sit off the coast to the north is stronger, & seems to possibly take over the flow out of the SW instead of the low to the south. This in real time would mean the wave coming out of the SW would be passed off from one low to the other. Due to the wave currently still east of the Sierra’s & Transverse Ranges, the hand-off between the two lows will result in a flow pattern switch where the upper level winds instead bring the easterly wave into eastern SoCal & then north into the Great Basin as the northern low takes over. This probably won’t favor convection making it to the SoCal coast all the way to Santa Barbara. However if the southern low holds on to it’s influence on the wave longer than expected, there is a good chance the easterly wave could keep moving further west. The Latest NAM 12Z is still not much help in determining where things may get active east of the mountains so it’s quite tricky. In the safe side, expect most of this stuff to be confined to the mountains, deserts & adjacent valley & coastal locations near these areas as well. It’s still a wildcard on whether or not these thunderstorms could wet or generally dry in the lower levels for SoCal, but I’d keep itin mind as we get things started. *MCS energy over AZ later this afternoon should be watched closely as the wave begins to turn west.* https://uploads.disquscdn.com/images/562a41d2dc0d54fcdd7d0165cef985c72db8196b26371dffecfeb7f358d8ba19.gif

    • CHeden

      Very interesting. Note the upper low off Cent Baja is slowly retrograding….most likely from a “push” from the easterly wave….albeit a weakening wave (ATTM)

      • 805 Weather (Camarillo)

        You’re right! & it will be interesting to see what comes of the newly forming convection today over western Mexico & Baja… Going to keep an eye on this all day. There is just not enough pull at the moment from the low to the south. Look at where it is bringing in moisture off of Mexico. Down near southern Baja then up again.

        • CHeden

          Hmmmm, depending on the offshore low’s precise position (longitudinally), which is/has been a quasi-recurring feature, it might also help steer Hilary either up the coast if the low sets up further offshore, or deflect it out over open water if the low hugs the coast. Right now, a retrograded low is a good sign for Hillary’s remnants to move up the low’s eastern flank. I too will be watching how today’s flow pattern sets up. Given that the “Hillary event” is only 7 days out, how today’s pattern evolves may act as a sorta “trial balloon” for next weekend’s setup.

          • 805 Weather (Camarillo)

            That would be quite the setup, probably a textbook remnant occurrence. I agree I think what will happen today though mid-week will be very telling on the next play.

  • CHeden

    For the first time in what seems like forever, high clouds have made it up to the north Valley this morning. Weak low pressure to our NW is starting pull up some juicier air from the SSE, with the flow expected to continue through Tuesday. Looks like the northern mountains will finally see some action, but I rather doubt anything will hold together over the Valley. Right now, I’m seeing Monday/Tuesday as the best days for storm possibilities as the low shifts inland then ejects NE.
    On the horizon, as others are noting, things do look quite interesting beginning around the 31st of July.
    What is now TS Hilary west of Cent. America, will languish pretty much in-situ for the time being under weak/non-existent steering winds before slowly drifting NW.
    As she moves farther north, Hilary will get caught up in anti-cyclonic flow from HP centered over WSW US and start moving almost due north off the California coast as the SW high’s ridge builds westward. With the low tracking offshore, this will put most of California in a juicy SSE flow pattern on the lows eastern periphery. While unusual, this type of setup is not unheard of. In similar past events, this amount of moisture can rapidly develop into localized heavy rains and storms depending on Hilary’s exact path…which in turn will hinge on how far (and when) the SW ridge begins it’s westward push. https://uploads.disquscdn.com/images/5dcbc54f4cb655e8799401c8703a708913b4ced5d3f40725482a9123b0e178c5.gif
    Here’s the GFS’s solution for around the 31st showing Hilary as it moves to a position off the coast riding N then NE as it goes “up and over” the ridge. https://uploads.disquscdn.com/images/c4afe7d224f7a54b0f7d760eaee9cb79c333c7d9426a2c70935a49ef57949d26.gif https://uploads.disquscdn.com/images/c4afe7d224f7a54b0f7d760eaee9cb79c333c7d9426a2c70935a49ef57949d26.gif https://uploads.disquscdn.com/images/c4afe7d224f7a54b0f7d760eaee9cb79c333c7d9426a2c70935a49ef57949d26.gif https://uploads.disquscdn.com/images/a5ed6abff22679d38747727f4e0e88336580eb9e787a6a2e39ff998296b9c4e5.gif

    • 805 Weather (Camarillo)

      Ridge placement is ideal for an influx into possibly the entire state, seeing that SE/SW flow has been pretty strong from the lows setting up shop off the south coast & Baja. I’ll have to check the ECMWF.

      • CHeden

        Given that both the ridge and Hilary are already present, the main question is a matter of timing for when/how far the ridge migrates west. It’s interesting to envision that should the ridge NOT develop quite as strongly, then Hilary’s track will shift more easterly….i.e. closer to to our coast…but with a bit less moisture getting entrained.

        • 805 Weather (Camarillo)

          Let’s hope so, I would not mind another sky like Dolores, but it’s wishful thinking even as close as we are to this one.

    • CHeden

      Here’s the correct GFS chart showing Hillary remnants going up and over the ridge. https://uploads.disquscdn.com/images/cfad5c2f626a63ace519dee39140e7c2ff49158dc1f033b819293e9177d02b9c.gif

  • 805 Weather (Camarillo)
    • Rainmaker (San Jose)

      I noticed the same thing last year. August tends to be the month the Atlantic fires up and the eastern Pacific begins to quiet down

  • CHeden

    A quick visual check of clouds aloft is showing some elevated Cu starting to develop around 20k’ as the morning wears on. Past ‘experience” tells me that instability this early in the day, even aloft, is often a precursor to more extensive mid-level convection later on. I’m thinking the Shasta area may see some activity from this pulse? The bad news is the air underneath is still very dry, so any lighting that does develop would also likely be dry. We shall see.

  • Thunderstorm

    Right now on the big hill fire lookout. Looks like insect drones!!! Has to be drones just too big. Check it out!!!!

  • Working on a post for later today. Fair bit to talk about regarding the next 10 days…

    • molbiol

      Are you going to comment on the poor performance of the models for Socal WRT monsoon influxes. Even the latest 12Z operational run has the monsoon door wide open during most of its run and yet it still has not verified this summer

  • Fairweathercactus

    NWS notes what I noticed yesterday about old cactus not being impressed with storm chances for the metro. II say its time to take them out.

    High confidence exists in the moisture pushing across
    the area, but the lift and instability is a bit more lacking
    across the model solutions. Some model solutions hang on to k
    index values in excess of 35 across the area, but favorable
    lifted index values remain over the mountains and desert.
    Precipitable water values are still healthy, in excess of 1.5
    inches nosing into Los Angeles and Ventura counties. For now, the
    forecast remains unchanged, but future changes might occur.

    • SoCal Al (El Monte-SGV)

      That’s it ‘cactus………..keep with the reverse psychology tactics, it just might work this time around.

    • AntiochWx

      It can still be saved right? Doesn’t congress have to approve the budget?

      • That’s the idea. But right now, it’s still slated for an 80% cut.

        • jstrahl

          Damn! Thanks for informing us.

    • Who Killed Kenny Strawn?

      Will the rotation be close enough to bring some action to Southern California? Dolores or Linda like action?

      • Hard to say now, but maybe. See my upcoming post…

        • Who Killed Kenny Strawn?

          Let me guess. GFS says “yes” and Euro says “no”?

  • Thunderstorm

    Did not know what the Fujihara Effect was so looked it up. Found this site very informative. How fujiwhara effect will toss hurricane sandy into U.S.

  • PRCountyNative

    New post!