Significant atmospheric river to bring heavy rain to Northern California this weekend

Filed in Uncategorized by on February 6, 2014 246 Comments

Special Update: heavy precipitation makes at least a brief return to N. California

Given the ongoing extreme drought conditions and the potential for a high-impact rain event in Northern California over the next 72 hours, I’ve provided the following (brief) update in the interest of keeping up with the rapidly changing weather pattern.

atmospheric_river

GFS simulation of major atmospheric river event over NE Pacific Ocean. (NOAA/ESRL)

 

Atmospheric River expected to bring heavy precipitation to Northern California

“Heavy” and “rain” are not words that have been used in the same sentence for a long time here in California, but it does appear that–for the first time in 14 months–some truly substantial precipitation is headed for parts of NorCal. I discussed in my last post the seemingly modest potential for an Eastern Pacific atmospheric river to impact California over the upcoming weekend, and in the meantime the numerical forecast models have trended considerably stronger with this event. Current satellite imagery depicts the early stages of what promises to be a significant precipitation event over the weekend.

atmospheric_river

Satellite-derived water vapor imagery depicting moisture plume associated with the atmospheric river extending as far south as the Hawaiian Islands. (NOAA/NRL)

 

Atmospheric rivers: a quick overview

“Atmospheric rivers” are long and narrow bands of highly-concentrated water vapor that occur in association with extratropical cylones (i.e. winter storms) throughout the Earth’s middle latitudes, especially over and near ocean basins. These features are often associated with extreme precipitation and flooding, especially along the mountainous western coast of North America (including California). To put the magnitude of these events in context: atmospheric rivers are (in aggregate) responsible for over 90% of global atmospheric water transport between subtropical and mid-latitude regions, and a single strong event is capable of moving an amount of water equivalent to 15 times the flow rate of the Mississippi River!

Those familiar with California weather and climate can attest to the critical role played by atmospheric rivers in driving wintertime precipitation extremes. I’ve noted in the past that California is dependent on just a handful of significant storm events for the majority of its annual precipitation, and this handful is usually associated with atmospheric rivers. California’s great floods in the historical past were almost all associated with atmospheric rivers, including the spectacular event of 1861-1862–which filled much of the Central Valley with floodwaters and inundated the fledgling state capital in Sacramento. Interestingly, scientists recently highlighted the important role atmospheric rivers have played in breaking many of California’s historical droughts.

One subset of atmospheric rivers affecting California are colloquially referred to as “Pineapple Express” storms, so named for their propensity to draw moisture northward from the Pacific Ocean in the vicinity of the Hawaiian Islands. Not all atmospheric rivers have such a trajectory, though most have some degree of connection to the subtropical atmospheric moisture reservoir. This weekend’s storm does actually appear to have a deep subtropical moisture tap clearly extending southward to Hawaii, so the upcoming atmospheric river does indeed meet the common definition of a “Pineapple Express.”

Short-term forecast through the weekend

Despite the absence of a strong synoptic-scale storm system near California, the extremely moist air associated with the incoming atmospheric river will likely produce heavy rainfall in orographically favored parts of Northern California. In fact, in the coastal mountains and foothills of the Northern Sierra, rain totals by Monday could approach or even locally exceed 6-7 inches. Rain totals will be considerably less heavy (but still impressive, especially by recent standards) along the North Coast and in the Northern Sacramento Valley. The I-80 corridor between San Francisco and Sacramento will be an approximate dividing line between heavy and more moderate precipitation (though the Santa Cruz Mountains could also see rain totals approach or even exceed 4-5 inches). Rain totals at lower elevations in NorCal may be anywhere from 1-4 inches. Southern California, unfortunately, will probably receive only very light rainfall from this event. As is often the case with subtropical moisture plumes/atmospheric rivers, snow levels will be very high for most of this event–well above 8000 feet in most cases.

GFS projection for accumulated precipitation from this weekend's atmospheric river event. (NOAA/NCEP)

GFS projection for accumulated precipitation from this weekend’s atmospheric river event. (NOAA/NCEP)

Rainfall of this magnitude will be capable of causing some modest hydrological issues in some regions, including the possibility for urban and small stream flooding. Main stem rivers will be very unlikely to experience flooding given the record-dry antecedent conditions, but since this will actually be the first heavy precipitation event of the season in most places the potential for 14 months of accumulated debris to clog smaller watercourses could present some problems if rain rates are high on Saturday. Some locally gusty winds may be possible at times this weekend, but in general the lack of a strong surface low will prevent strong winds from causing significant problems.

By Monday, ridging will start to build back in across the Eastern Pacific, but a secondary atmospheric river may brush the far North Coast (near the Oregon border) will some additional significant precipitation early next week. Current indications are that most of California will trend toward drier conditions once again, but the overall pattern in the Eastern Pacific will likely be more progressive that it has been in months. I’ll have more details on this after the weekend storm passes through.

 

Will this weekend’s heavy rainfall end the drought?

In a word: no. There will likely be beneficial increases in streamflow and runoff into reservoirs following the most intense period of precipitation this weekend, and this storm should (finally!) put an end to the Northern California fire season, at least for a little while. However, as the National Weather Service in Sacramento has helpfully illustrated, the ratio of the amount of precipitation expected to fall this weekend to the long-term precipitation deficit is roughly the same as the volume ratio of a 10-ounce coffee mug to a 5-gallon bucket. So: while this weekend’s atmospheric river may bring more than the proverbial “drop in the bucket,” we still have a very long way to go before our extraordinary drought conditions are substantially mitigated. Stay tuned.

© 2014 WEATHER WEST

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  • Fiendishly

    Even if it’s just a drop in the bucket in the grand scheme of things, this is truly joyous news, just the same.

  • Utrex

    Fantastic write-up! At least this storm will put a dent in this drought.

    Oh, and for the past few weeks NOAA’s march precipitation forecasts show above normal rainfall! I have a hunch we’re just in the beginning of the rainy season.

    • snow755

      No it. Won’t put a dent the drought we need. 10 more storms like this too make a vary big. Dent in the drought. It looks like things will dry out after next week

      • Loyal Brooks

        A dent is a dent. If we need 11 of these storms, and one comes in, then we only need 10 more – that’s a dent.

      • Peter Gambrill

        Instead of framing California’s situation as drought conditions vs. normal conditions, at this point it might more informative to talk about modest drought vs. severe drought vs. catastrophic drought. This is especially true when discussing, say, the localized water supplies of many small communities, where a storm like this will make a very big difference between getting through the summer and running out completely. This also applies to cattle ranching, and the health of many local ecologies and fisheries. This storm may make only a “dent” in the overall water deficit, from the perspective of state agriculture and municipal water districts, but it’s an important one for the state nonetheless.

        Ignoring the question of how much precipitation we’ll get in late Feb, then March and April (and whether this is the beginning of a new, much more favorable pattern), this rain makes me very positive–if for no other reason than it makes a catastrophic drought that much less likely.

        • lurky mclurkerson

          Yes, this.

          Droughts, we have sometimes, and we get through them.

          Getting through this particular drought was looking rather dubious to me. So if all this does — and more, I hope, like it — is push us from “absolutely catastrophic level of drought” to “sucky drought that requires us doing our best to get through it,” I’ll certainly take the shift toward “sucky.”

          This won’t solve it, and it may not pull us totally from the edge by itself, but I feel more hopeful right now about what we’ll be like in August than I did before. It’ll still suck, but I was having a hard time picturing how a huge chunk of this state could actually make it at all, with zero water allocation from the state water project. It’s an awfully long way to truck water… from where, at that scale?

          Anything that brings us to mere “drought” is a meaningful dent, not that I can blame the NWS for stressing that this isn’t bringing us out of drought. It’s not, and there are a lot of folks who really don’t seem to understand just how dire this has been; I certainly don’t want to see a bunch of folks figuring we got a bunch of rain so it’s all fine. I will still be busting out some celebratory spirit this weekend while I watch the rain. Maybe my knuckles will even stop cracking and bleeding from the dry, for a bit.

  • Dan the Weatherman

    Even though the snow levels will be higher due to the subtropical origin of the air mass, the heavy orographic rains should add at least some much needed water to the lakes and reservoirs that are running low in the shorter term such as Folsom Lake even if there isn’t as much snow accumulation in the Sierras this time around. Hopefully, more snow falls later in the season that helps fill the lakes and reservoirs even more as we approach the dry season.

    • kurt frohling

      I agree. Even without a big bump to the snowpack the runoff will be a boon for water catchments that have been in massive decline for months. Regarding late season snowfall, in my part of the state (Butte County) we can get some of our heaviest snows in late February and well into March. This morning watched the snow turn into rain as snow levels quickly moved uphill, but that rain is beautiful!

      • Dan the Weatherman

        I feel that we are due for a back-loaded season this year in which the majority of the precipitation falls from January on into the spring months (in this extreme case from February onward). Recent years have tended to be front-loaded in which the majority of the precipitation has fallen during the fall and early winter, and then has dropped off as we get into February and March with drier than average springs to follow.

    • Azmordean

      Actually I think this will be a substantial snowpack builder in the actual High Sierra, which is well above 8000 feet in a lot of places. I think anywhere over 8000 will be mostly (though perhaps not all) snow in this event.

      • lurky mclurkerson

        It could happen on the high peaks, but most of the high sierra is pretty well south of Tahoe, so I think the real question is where the bulk of precip winds up focusing. Seems like most of it is really supposed to be too far north to hit most of the real high sierra.

        Apart from Shasta and a couple of peaks in Klamath or the Warner mountains, there’s really not that much super high stuff north of the I80-50 corridor.

        • Loyal Brooks

          By far the wettest areas of the Sierra exist over the N third of the range. To simplify why this is so, we may consider orographics, where mountain ranges cause air to lift, cool, and condense moisture, releasing its rain and snow as it passes eastward.

          While this process is well-known, less well-known is that rainfall increases with height up to about 8,000,’ the level at which most moist air is carried inland from the Pacific. Above 8,000,’ there are diminishing returns.

          The other reason the N Sierra are so much wetter is because it lies farthest to the N, receiving moisture off the Pacific most frequently.

          It may seem like there is much more snow above 8,000′ early summer in the High Sierra, but that is only due to a lower temperature, melting the snow more slowly, not because of greater snowfalls.

          • lurky mclurkerson

            Oh, agreed, ultimately.

            I just really meant regarding snowpack for this particular warmish, northish system, it seems unlikely that the highest peaks, where it might stay cold enough to retain much actual snow, are going to get much precip generally out of it, though we’ll see — I’m seeing radar returns a little farther south than I figured today, so maybe they’ll get some.

            The highest high sierra aren’t necessarily as prone to huge amounts of precip, but they do tend to hold the snow for us for quite a while. I hike/camp up there a lot, it’s those long lasting snows that let you filter water for the hike. And there’s nothing like feeling dusty and hot, hopping into a tiny lake when you can see the snow melting into it 😛

            I think that the most wet-snow depth I’ve ever seen fall was more around Tamarack, so still south of Tahoe by a bit, but not what we usually think of as the high sierra; the mountains as you go north get lower mostly, but also get more regular precip and snow to lower elevations. Certainly there’s a lot more that usually falls in the north, but it isn’t usually retained as long into the late summer, either.

            We need it anywhere we can get it, at this point. I’m fine with this remaining a largely rain event, even, so long as we get some runoff into some reservoirs. Folsom has been looking like hell for months, and I’ve never seen the American river so low as it was in early January, in the whole time I’ve lived by it, even in September.

          • Loyal Brooks

            Yes, I miss my hikes into the high Sierra myself – from high up in the Yuba drainage to the Mokelumne Wilderness to Yosemite’s high country to going into the backcountry in Sequoia NP.

            The areas in CA that are in the most dire need of precipitation, rain or snow, is in the NW, especially the coast ranges (all of them), the Shasta-Trinity area, and the N third of the Sierra. Precipitation is urgently needed everywhere, of course,

            The most serious soil deficits are found in those areas. There are areas in Butte Co. that need 26+ inches of water to percolate into the soils just to return them to normal. Now dry springs will return to life when the groundwater is recharged.

            To visually see where the water is most needed, check out this avg. precip map of N CA. While keeping in mind most of the area has received 2-6″, the blues show just how far behind N CA has become. (I don’t mean to leave out S. CA.).
            http://www.wrcc.dri.edu/pcpn/ca_north.gif

          • lurky mclurkerson

            Yep, definitely, the ecosystems of those areas rely on fairly high (by CA standards) annual rainfall. And they’ve gotten nowhere near enough to sustain those ecosystems. While a lot of those species are well adapted to survive a period of dry, this has been just a whole ‘nuther scale — and while a lot of the longest lived things like the coast redwoods will probably make it ok, there’s a whole lot that needs the water to survive the year, even without considering the direct needs of people.

            Our only really _healthy_ salmon runs at this point are in those regions, too — they still run up the American and even a little up the San Joaquin watershed, but that’s been iffy for a a while. The salmon runs in the Trinity area sustain a huge number of people who otherwise really have little income, lots of still-struggling tribal lands in there.

            I worry for our watersheds and especially our groundwater generally. Reservoirs, at least people can see and get panicky over; most people, unless they have well water in a region being hit hard, really don’t think about the groundwater much.

            Here in urban Sacto, I’ve been worried about this scale of drought sending our legacy, actually very large and old “urban forest” down on people’s heads this year, if we didn’t get some kind of relief. They can only tap so deeply, and not all are terribly resilient species.

            All of which rambles out to say: YAY, water type stuff from the sky!

          • lurky mclurkerson

            Honestly, when I think about it, us Californians have had a nice deal for an awfully long time — rain along the north coast and into the northern foothills, lots of rain and snow into the northern Sierra and the Trinity/Klamath etc, that buffers us as the rains taper off, and then the high sierra snow — not always a ton in total, but long lasting — to get us through the summer/fall.

            We’ve been very lucky, with the distribution of _natural_ water storage.

            Fingers crossed that the basics of that hold over time, because there’s no way you could build enough storage capacity to make up for that well-timed and huge-capacity water storage that we’ve been lucky enough to be provided by natural processes and geography, thus far.

  • redlands

    Redlands, Ca Weather Update — Southern Cailfornia —- I only received 0.09 of rain — so February wont go rainless —- Was nice to get rain — was cool — but 0.09 of rain is really measly — looking for a 0.50 to 1.00 storm for a day. Is this the last of the rain for the next 7 days for Southern Calif — appears to be on the local tv news

    • Sunchaser

      .30 here in the South part of Glendale with this storm and a total now of 1.52 for the season….

    • .29″ yesterday in Santa Maria. Brings the total for the week to .48″. The ground has some moisture in it, at the surface at least, for the first time this season. Rain is passing to the north but so close I can almost see it. If it would just shift south 50 miles……………….

      Congrats to those further north who are getting some much needed heavier rain. Enjoy it!!!

    • redlands

      Redlands, Ca ended up getting a bit more rain — grand total from this storm was 0.12 of rain —

  • lightning10

    It’s looking more likely like a big time heatwave is on the way for So Cal once this last energy moves through.

    • Dan the Weatherman

      I don’t think a heatwave is going to occur, but temperatures may get up into the upper 70’s to near 80 later next week with some degree of offshore flow. Hopefully that doesn’t last long, and it may not, since Daniel mentioned above that he sees indications that the pattern in the eastern Pacific is likely to be more progressive than it has been.

      • Bummer. Last night was the first time I’ve used my windshield wipers on the drive home in quite some time in San Diego.

      • CalNative

        Would someone please explain what “progressive” means in this context? Thanks!

        • Loyal Brooks

          Progressive, used in the meteorological sense, refers to the interrelation of the positions of the jet stream, with ridges, troughs, and areas of zonal flow (W-E) in middle latitudes. During ordinary times, ridges develop, break down, or move along in an eastward fashion, along with everything else. Areas of zonal flow off the Pacific brings needed moisture inland. When the weather is being “progressive,” these features move along with the overall flow of of moving eastward (around the globe). Ridges and troughs progress, that is, move along, and are not stuck in one place, such as our RRR has been stuck for 14 months.

          • CalNative

            Thank you very much for the explanation.

  • David

    Im so glad Cali is finally getting some much needed rain. It would truly be remarkable if by some miracle northern California could approach near normal rainfall when all said is done. One could only hope the next 2 or 3 months bring above normal rainfall. It used to drive me crazy when when it wouldn’t rain in So.Cal during the winter andI would have to wait till next year which looks like that this year but at least up north is getting what they need. Now lets see what next year may bring with a possible El Nino.

  • rainscout

    Bring it in Pacific!!..great sheets of rain!! My heart soars like a hawk!! I think I actually heard a great sigh of relief from the redwoods and my river finally may be able to be heard again…sure hope more will follow but for now this is great news and I hope the Santa Cruz Mtns. orographics kicks in big time!!

    • Loyal Brooks

      Your enthusiasm is enjoyed by all who love the rain, and love finally see it coming down. I’m glad, and I only KNOW it is raining where you are due to these interweb machines we have.

  • Zepp

    Our hoped-for foot of snow has fizzled–there’s less than a 1/4″ on the ground in patches. But we are getting a nice light soaking, and even if we don’t get the snow, it will at least knock down the dust and the fire danger. If what I’m seeing here is indicative, there won’t be much in the way of run-off. In fact, at this point, none. Granted, we’re amongst the hardest-hit in the state: since 1/6/13 we’ve had 2.5″ of rain, and over those 13 months since we should have seen (based on average) about 58″. A local soil hydrologist tells me we need two FEET of light, drenching rain just to bring the forest floor up to normal moisture levels. At which point we will start contributing to surface stream run off.

    • Fiendishly

      Out of curiosity, where are you located?

      • Zepp

        South slope of Mount Shasta, at 3,300 feet.

        • Steve

          I think the big storm is heading your way now. Should have 4 – 6″ (rain) by Monday.

          • xeren

            and then several more inches in the system right after that

          • Zepp

            That’s about what I’m hoping to see. Snow would be more beneficial for the surrounding forest (think of it as a “time release” rehydration of the soil and it also makes a good sponge for subsequent rainfalls) but on the other hand, I don’t have to shovel rain. So I can live with six inches of rain…

    • Xerophobe

      If you’re near McCloud at ~1000m (well Olympics are starting) I think you will be near the snow/rain line. Might be snow then rain. Don’t worry it’s a comin’

    • Coldspot

      Only received a measley 0.57″ here in western Siskiyou county as of this am for the last 24 hours. But more on the way.

      • Zepp

        We’re benefiting from orographic uplift here as the storm sweeps around, and it rained fairly heavily all night. But it’s a warm rain: snow level started about 3,500′ and it up to 6,500′ now.

        • Coldspot

          Yeah bummer still for the ski area.

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  • Dan the Weatherman

    The latest ECMWF weekly forecast as shown by Brett Anderson (Accuweather.com) just shows CA warm and/or dry right on through the first week of March. I don’t know that I quite buy that at this point in the season, and I really believe that it will be wetter from now on than it was in December and January.

    http://www.accuweather.com/en/weather-blogs/anderson/any-break-in-the-cold/23053173

    • Kamau40

      It seems to me that the flow pattern has shifted enough so that we should get more rain/snow here on out. You’ve mentioned in an earlier post that we should be getting the back loaded storms going into at least the first part of spring. Perhaps, we have just gotten past the peak of this current drought. Although this drought will not end this year. Also, looking at the long-long range forecast, NOAA’s Scripps Institute on Feb 3rd is predicting a major El Nino for the winter of 2014-15 which I have been showing climate models are still showing an El Nino will be developing soon. Please see reference on mammothweather.com. They are showing SST anomalies in the Pacific during Dec, Jan, Feb ’14-’15 will be at least 1.5c which qualifies as a strong El Nino event. This is great news which is something we all can look forward to down the road.

      • Dan the Weatherman

        That would certainly be great news if that verifies, and I saw the El Nino possibility mentioned on mammothweather.com. A major El Nino event has a very high likelihood of bringing well above average precipitation to much of California.

  • craig matthews

    This upcoming atmospheric river set up looks similar to a couple of events that occurred early last winter in November and early December 2012 before the RRR took over. I still think that the ridge projected to build off California in the next week or two will not be another RRR. I think we are in the midst of a major change. Even if a ridge builds over California next week it shouldn’t last too long. Flow pattern across the pacific is becoming more and more zonal and I think we will see more atmospheric river set ups between now and april. Hopefully the longwave trough will come closer to the west coast next time and put socal in the action.

    • Loyal Brooks

      OK, Craig and Dan TW, you guys are holding up a more positive outlook than I can actually find myself. No matter what model, projection, evaluation – whatever – what I keep seeing is that the extreme ridge of the west coast is being replaced by a low amplitude and low-latitude area of high pressure.

      This feature is more of a concern for S CA, as it does not appear strong enough to affect N CA too much – as was the case previously. I believe what I am seeing is the usual “H” that sits well off Baja and has no where to go is not budging on future models, except for possibly a few days around Feb 20-23, or so. The GFS signals a deep low to drop from the N into S CA, for a possible repeat of cold, dry air…but this is a long way out. Earlier today, it did not have this feature at all.

      There is one ray of hope that I do find, and that is a -PNA pattern thru most of Feb. When negative, it is easier for the flow in the Pacific to fluctuate and bring N and C CA normal spells of rainfall. Maybe this parameter will save S CA from a near “shut out.”

      • Xerophobe

        Good point regarding the -PNA. All of CA and NW needs rain.

      • Dan the Weatherman

        We are still in a -PDO, +AMO, ENSO neutral pattern, which leads to below normal rainfall in mostly the southern half of CA, so it is no surprise that this low latitude ridge is forecast. I think this is a more classic set up during this current regime, as opposed to that monster of a RRR we were dealing with earlier. Socal will likely have more dry spells from here on out than Norcal, but I think there will be some wet periods at times as well in Socal, but a good deal more relief for Norcal compared to the first part of the season.

        • Loyal Brooks

          I believe you are right overall. I was just pointing out that the PNA teleconnection is second only to the El Nino in affecting the weather of CA, especially in the wet season. It was extremely positive in January, which would suggest an very warm period – which happened. There was a brief dip to negative around Nov 16, and that was a previous rain spell (Folsom dam near Sacramento received 0.55″ of rainfall on Nov 16, the wettest day this rain-year up until yesterday). Here is a link to the index. We want it negative for rain in CA!! Thankfully, there is more time in Feb where is it forecasted to be negative. http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/pna.sprd2.gif

          • Dan the Weatherman

            -PNA is definitely favorable for bringing rain to CA as it usually means a trough in the west and like you said a +PNA usually means ridging. +PNA often occurs simultaneously with a -NAO pattern in which there is a huge ridge over the west, a trough in the Midwest (often with a Hudson Bay Low) and a Greenland Block (high latitude blocking over the north Atlantic and Greenland), which brings mild to warm weather to the west and cold weather to the east.

  • rainscout

    Well i wiil say this..Craig matthews and Dan the Weather Man have been positive about a possible change for quite awhile..I found it difficult to embrace their optomism when things where so locked up in the RRR..but I will say that here we are on the cusp of at least one good rain event in 13 months…sure hope it leads to more and even if not..this is a beautiful sight..real rain on the roof!!.keep up the positive post ..who knows what lies down the road…but i sure hope it is nothing like the RRR!!!

    • Loyal Brooks

      Yes, it is better for this board to be positive. It was difficult to be positive for along time, though. I feel relieved by the negative phase of the PNA, which is surprising no one mentions in here, it having SO MUCH influence of weather over the west coast. It has gone sharply negative now – and look, it’s raining. I posted a link to show most forecast models keep it negative for most of Feb, for more chances of rain across the state. Here is a more general link from the climate prediction center for PNA, but the left side has a menu to select other indices for anyone who is interested: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/pna.shtml

  • Mendodave

    1.66″ here in Little River since 2/5, forecast another 2/3rds” tonight, 1.5″ tomorrow, 2.10″ tomorrow night. you guys are getting pretty damn good with the rainfall estimates. my trees are dripping wet, and it is a glorious sound!

  • redlands

    Only 0.12 from this storm that just passed Feb 6/7 – 2014 in Redlands, Ca Southern Calif

    • Dan the Weatherman

      I only picked up a measly .12″ with this storm here in Orange, too. Enough of these ridiculous July level accumulations for what is normally the heart of the rainy season down here. Bring on the BIG storms!

      • sdmike

        Sadly, only .12″ here in Carlsbad. Most of the precip seemed to go by just to the west of us and looks like it hit South County and Baja Mexico. 🙁

        • Dan the Weatherman

          I noticed that Carlsbad received less than the other areas and so did Del Mar with only .01″ despite 1/4″+ totals on either side of the area.

  • rainscout

    Thanks to Loyal Brooks for all the great information and links..good education for me as an armchair weather person..but I will ask..what is the laymans explaination for the negative vs. the positive PNA as it relates to west coast patterns? If you look back to oct. and part of Nov. 2013 it was negative as well but they were almost bone dry months..I know there were many other factors..just showing my relative ignorance..thanks again Loyal for all your incite and concern for West coast weather..as well as weather in general as of course as you have said..”it is all connected”….just checked my rain gauge..2.5″..so far a little shy of their predicted totals but we still have some time to go..the ground is finally getting wet here!!!!

    • Loyal Brooks

      Your flat-out enthusiasm and rain-gauge reports are very welcomed here. Everyone’s reports are welcome!! If it weren’t for those of you who do give personal tallies – or ones that you find – people like me would be left only with just lists of totals/reports. All of you here add color and flavor to these tallies!

      No one is really certain why different oscillations – teleconnections – sway back and forth the way they do, and how they interrelate to one another. New ones are found routinely, and older notions about how the teleconnections influence our weather are dispensed with. This has been going on for many, many decades. Weather is a very transient thing! These oscillations are in the realm of climatologists.

      The main one for CA is the ENSO. After that, it is the phase of the PNA. They are related, but it is not understood just how. Simply, +PNA means ridging over the west coast, with the jet stream steering storms N-ward over BC. -PNA is the opposite, a tendency of troughing over the west coast. I know brief, but limited space.

  • Dogwood

    Diminishing to a mere spectator event here in San Jose, after Thursday’s .75, yesterday tallied .20 and so far overnight into mid morning Saturday, .05″ as this thing appears to be breaking up overhead for now.
    Congrats to Mount Tamalpias with over 6″.
    Do get me wrong, though, it’s flat out beautiful weather outside where I am!!

    • Azmordean

      Yeah pretty pathetic here in Silicon Valley so far.

    • Matthew Gudenius

      Wow, what a difference north vs. south of the bay makes…
      Here in St. Helena, I’ve been begging for rain (we are already a hotter and drier location than most of Napa Valley)… this current system has not been heavy, but has been going consistent for a few days now.
      2″ and looks to keep going into tomorrow…

  • rainscout

    Thanks again Loyal…I kind of thought it was a more scientific way of saying High and low pressure..as you say much more involved than just that..just trying to make sense of all the Abbreviations and Weather terminology..

  • Ricky Wogisch

    Hate to say, we have had almost 6″ of rain since Wed here south of Santa Rosa…..1″ of it since 9 am today with no let up!

    • Dan the Weatherman

      That should help out with any lakes or reservoirs in the area, if there are any in that region. I am not familiar with the Santa Rosa area as I am from Socal.

  • Azmordean

    Very conflicting rain reports out there for the South Bay. Most sources I can find show only show around a tenth of an inch for San Jose, but NBC just reported a 1 inch total?? The tenth is more accurate from what I can tell. SoCal actually has more rain in places than San Jose for this event. Looks like a sharp cutoff to the precip somewhere around SFO. So far this is a complete non-event in the South Bay – nothing compared to the Thursday event. Hopefully that will change but it looks like things set up a bit north of model predictions (or the models just completely missed the usual rain shadow).

    Glad to hear SF north is getting some badly needed precip though!

    • We have been very heavily rain shadowed here in the SF Peninsula lowlands–weekly total here is around 0.7-0.8 inches and 24-hour totals around 0.3 inches. Might pick up some between now and Sunday, but this has definitely been an orographically-driven event. Some spots are already at 5-6+ inches…

      • Azmordean

        Yeah it’s just kind of odd, usually a system with this much moisture manages to push a bit more over the Santa Cruz mountains. I’m thinking the best chance may be tomorrow when the last burst comes through with the front.

        • Loyal Brooks

          This time around, it is not dynamic atmospheric forcing that is driving the rainfall (which is the usual case). Atmospheric rivers are a different animal – this is heavily orographically driven.

          Most typically, rains are from a combination of dynamics and orographics. This time, most of it is orographics, in contrast with the event last Thursday which was highly dynamically driven.

          • Azmordean

            Right it just seems odd that news continues to call for up to 2″ in San Jose when we’ve basically gotten a few showers and not much else. The sun is actually trying to poke through here in Mountain View. Very disappointing for a weather lover but I suppose I knew that before moving here :P. Next time I will storm chase I guess.

            Still some hope with the front Tomorrow though since that should provide some dynamics.

          • Loyal Brooks

            I was just looking at the SF discussion, and they say “up to 2″ elsewhere” and considerably less towards the south (Monterey Co.). From the Reno discussion, they are still maintaining that this river will punch up as dynamic forcing (by way of a cold front) begins to sag south. That raises the the chances for you not to entirely miss out down there in the S. Bay overnight tonight and into tomorrow.

            Hope that helps. It isn’t particularly exciting here either – gray skies all day, but we did crack 10F a while ago. It has been trying to snow all day. Tonight, a large dome of high pressure will settle over the area for renewed teens and 20s below zero readings.

  • c33f

    Tweet from NWS Bay Area shows 72 hour rainfall total at Mount Tamalpais/Middle Peak exceeds 10 inches.

    • I’m pretty sure that obs station was offline for a matter years until recently.The south and west slopes of Tam do see extraordinary orographic enhancement. If this is accurate, it’s extremely localized and probably associated with totals in the 2-5 inch range in the nearby lowlands. Does look like rainfall in the Bay Area is picking up once again, though. Definitely some impressive 72-hour totals in the North Bay.

  • craig matthews

    That sub tropical ridge off socal is really upsetting the whole situation for people south of I-80. Those impressive amounts that are shown have us drooling down here in Monterey county, just 100 miles south. We managed to get 1 inch in big sur due to the orographic lift over the mtns. But inland Monterey county remains dry. Hopefully the frontal boundary will hold together enough as it drapes over us tomorrow.

    • Tonight/tomorrow should be the biggest push for those in the south, though totals will still pale in comparison to the Sonoma County totals.

      • craig matthews

        We must have had a warm front passage around midnight down here because our overnight low of 52 occurred just after sunset then the temp jumped to 63 around 1am. Now its a balmy 65 and the sun is poking through the clouds here as well

        • Xerophobe

          Same here near Monterey. Windy but rain stopped early and wasn’t that much just seemed like “warm front” foreplay. Golf was halted for awhile for wind and I was thinking yesterday we’d have rain delays.

  • Amazingly enough, a Flash Flood Warning was just issued for the urban areas in Sonoma County. Precipitation over the past 12 hours has been quite heavy, and I’m guessing that the extremely dry soils are still not allowing for much infiltration. With additional moderate to heavy rainfall moving in over the next 6 hours, there could actually be some significant problems in that region. And here–a mere 65 miles to the south–the sun is poking through the clouds.

    • Xerophobe

      This kinda reminds me of the last “Miracle March” when the demarcation of precip seemed to be within a half degree of latitude. Either you were on the ‘good’ side or ‘bad’ side.

  • craig matthews

    It will be interesting to see what will become of that large pool of warm waters in the northeast pacific south of the gulf of Alaska now that the flow pattern has changed in the northeast pacific. A long fetch of prolong westerlies, or southwesterlies might push that warm pool closer to the pacific northwest coast. If that warm pool is shallow it might just disperse, but who knows.

  • lurky mclurkerson

    My highly scientific (and only mildly slanty) Cheap Plastic Kiddie Pool Rain Measurement Device has a good 1.25-1.5″ since I set it out Thursday morning — really just to collect whatever I could for the garden, in case we had a bunch more dry coming soon. I also put every bucket, big pot, etc I could gather out under some roof runoff, I think the neighbors think I’m weird, but they probably did already. Red Bucket #2 is nearly full, but it’s been collecting from the garage roof. 😛

    Not bad, so far, in Sacramento. Not terribly heavy thus far, but sometimes pretty solid, and really very steady. And it looks to me like it might really hone in on this corridor as we go, so more is on the way. I’m sure most will wind up in the coast range and Sierra foothills on up, we just don’t have the geography to support those kinds of rains very often in the valley, but what we are getting down here is sure nothing to sneeze at.

    • Xerophobe

      I used to have rain gauges, but got to anal about placement and wind, etc. I have a similar method to yours and I can tell if it rained a lot, some or a little. I used to get ‘mad’ when I thought we had a lot of rain over night and it was only .25. Yes I have issues.

      • lurky mclurkerson

        Yeah, I figure I don’t generally need to be that accurate, really. “Tiny” vs “Some” vs “Pretty darn rainy” is about as far as my patience level takes me, I always figure I can look at nearby places if I want the real score.

        Closest actual rain gauge (KSAC) has an official inch for the “week” now, so not bad.

        The lowest of these clouds are moving really fast, I wish I had something that could catch it on video. Not too much gusting to the ground, though some decent gusts for sure, but that lowest bunch of cloud deck is just _booking_. Unusual number of seagulls up here today, and they’re all going sideways. 😀

  • lightning10

    0.22 for my area with the last storm. The best dynamics stayed slightly offshore.

    • Dan the Weatherman

      You did better than I did as I only received .12″. That is not saying much, though.

      • lightning10

        That upslope helps Whittier out. If it wasn’t for that it would have been around 0.10

  • Boiio

    Seems as though Marin and Sonoma counties are the big winners in this storm. I’ve received nearly 6″ since yesterday morning here in San Anselmo. The Middle Peak RAWS atop Mount Tamalpais has received over 10″ in the last 48 hrs. Great news for our local reservoirs!

  • lightning10

    Got to keep an eye out on the GFS. Been on and off again with (it hurts to say this) late Winter cold snap. A sharp through digging down brining some cold air.

  • Zepp

    About five inches so far here, all in the form of rain. Steady, moderate rain, exactly the best we could have hoped for. Unfortunately, the ski park got about nine inches of snow, and then it turned to rain and with the snow level climbing today, they aren’t getting any breaks.

    • Zepp

      One thing about living in the mountains: if you don’t like the weather, move over five feet. My gauge said 4.93 inches, but the official gauge about a quarter mile from here says we have a total of 0.98 inches. We much have caught some microbursts. I believe my gauge, because we had puddles in the back yard, something that happens with our poreous volcanic soil only in exceptionally heavy rains. But, alas, it was a very localized phenomenon. It’s 40 and drizzling here, raining at the ski park, which is helplessly watching its 14″ of prized snow melt into the ground rapidly.

  • Baroclinic leaf developing out ahead of the wave due in overnight. Rain rates will probably peak as this feature comes ashore:

    • Ricky Wogisch

      Is there a new blog update soon, hope so!

  • In classic atmospheric river form, there is a risk of flash flooding in the Marin/Sonoma/Napa area tomorrow, yet parts of the South Bay (50 miles to the south) will see only light precipitation overall, and SoCal will remain essentially dry. The moist Pacific plume will gradually shift northward through the coming week, keeping precip mostly north of San Francisco and eventually north of Eureka by the end of the week. There are some signs that a high-amplitude ridge may try to build–once again–off the West Coast during week 2. For now, let’s stay focused on the locally very heavy rainfall over the next 24 hours…

    • Kamau40

      It has been raining very heavily since yesterday here in Napa, Ca. Rivers/steams are rising and with the next wave of energy we should see the peak between late tonite and tomorrow morning. This is the kind of weather we should have been getting all along. Would love to see So Cal to get this nice rainfall too. March is still looking like a wet month according the latest CFSv2 climate models, hopefully that will verify.

      • Dan the Weatherman

        We should be getting that kind of weather down here in Socal this time of the year as well at least on occasion even in a -PDO, +AMO, ENSO neutral regime. There has been absolutely no heavy rain in my region for this entire season so far and I feel like we are being left in the dust!

        • Dogwood

          As per usual, and if it’s any commiseration, San Jose is dry too. No rain since .05″ early in the dark of the morning. Streams of fat low wet looking stratocumulus all day, with no mechanism to make them rain.
          Earlier today I thought it was great. Now I’m feeling ripped off.

    • Dan the Weatherman

      I hope that is not the RRR trying to rear its ugly head again during week 2. I have only recorded .17″ of rain down here in Orange for the month so far and no meaningful rain is forecast down here again anytime soon, except for possibly a bit of drizzle (ridiculous for February).

  • Amazingly, Portland, OR is currently enduring a pretty spectacular ice storm on the north side of this atmospheric river. Wild!

  • Michael Wiley

    When will calculations of the PDSI before and after this event be available? I’d love to better understand the impact of this AR.

    • I’ll definitely check that out for the next update.

    • Loyal Brooks

      PDSI = Palmer Drought Severity Index. Measure of the amount of moisture in soils. Some areas were extremely depleted from normal, on the order of 26+ inches in some areas. Just soil moisture alone.

  • lurky mclurkerson

    For whatever it’s worth, downtown Sacramento broke its daily record rainfall for Feb 8th. Came out at 1.28″. Old record was from 1985 at 1.17″.

    Quite a heavy band came through early this morning, at least for the valley. Looks like we’re heading toward a break for a little while now, though.

  • Loyal Brooks

    Interesting to note that that extremely high 9.91″ in 24 hrs on Mt. Tam was taken out at the 4am QC (Quality Control). They do not feel it is accurate. This was done by the CA-NV River Fcst. Center.

    • I had the same suspicion myself.

      • Boiio

        That spot consistently gets at least double the rain of the surrounding areas. The marin municipal water district has a rain gauge a few miles away and a couple thousand feet lower that also receives heavy rain totals, which are generally pretty close to those up at middle peak. Granted 19″ in 48 hours is extreme, it’s not unheard of up there during these types of events.

        • I’m curious what the unofficial gauge at Lake Lagunitas has to say. Part of the problem is that that Middle Peak gauge on Mt. Tam had been offline for years, and it’s possible that we don’t have a good handle on what the typical scaling factor is relative to other local sites. Still, I think 19″ is probably at least 30-40% too much, since as moist as this plume has been the haven’t been any spectacular dynamics. That said, there are some very impressive rain totals in a fairly narrow band from Sonoma County up into the NE Sierra foothills…

  • Robin White

    Nothing here in the Monterey area but warm advection mist. No radar returns to speak of, just a constant drizzle being squeezed out of a sky where moon and stars were easily visible. Enough to accumulate in puddles but not enough to run down the streets. Glad for the heavy rains up north, but this was a whole lot of nothing on the central coast.
    Robin

    • Azmordean

      Same in the South Bay pretty much. Still some hope we’ll all see a quick .25 – .5 when the front comes through later today. But considering models showed 1.5+ for us this storm was a total bust down here (though a boom in the north!).

      I had no idea a rain shadow could be this strong with mountains as low as the Santa Cruz. Places as close as Burlingame got an inch but maybe a tenth down here.

      • craig matthews

        Been a steady heavy drizzle here in big sur and managed to get .44 overnight from lots of tiny raindrops. Seams to be a stratoform event down here with a lower cloud deck banking up against the sw facing slopes.

        • Xerophobe

          I’m seeing some good stuff on the IR that should bring a dose of rain to us soon.

  • darrenking

    Flood advisory has now been issued for Sac County. It’s been raining non-stop, often heavily, here in Folsom, east of Sac, up against the foothills, for a couple of days now. Some portions of streets and parking lots now underwater.

  • TheNothing

    I know the south isn’t getting this moister plume but wow, the central valley foothills are getting walloped.

    • Sequoia

      We’re done with rain in the southern Sierra foothills. Maybe got 1/2 an inch in the past 3 days, a few lingering clouds and that’s about it.

    • lurky mclurkerson

      Agreed, some of the totals coming out of the area from roughly Butte Co down into Calaveras are really impressive, really centered on the stuff right uphill from Sacto and nearby. Some big rainfall amounts coming out of Nevada, El Dorado, Placer…

      Good for the reservoirs, but that is a lot of water to deal with all at once.

    • redlands

      Yes — Southern Calif isn’t getting nothing — just clouds we need some rain

      • Dan the Weatherman

        We need to get something substantial down here very soon. I am really fed up with the inability of it to rain down here as of late! Many stations only have received about 1.5″ plus/minus a couple of tenths for the entire season since July 1 and this is after the awful second half of winter last year. The hills are brown as if we are at the end of summer as opposed to being greener like they should be by now.

  • TheNothing

    Folsom lake has almost risen 8′ in the last two days and is filling quickly as I type this.

    • Xerophobe

      That’s great news. Hopefully there will be another handful of events like this one for you for the remainder of the rainy season. I know Roseville and especially Granite Bay are in a world of hurt without Folsom

      • Dan the Weatherman

        I figured a heavy rain event would help Folsom Lake, and that is great news to hear that the lake is beginning to fill up. If we could just get more storms between now and the end of the season, that would definitely put a dent in the drought, but it will take longer to end the drought completely.

    • Loyal Brooks

      According to the CA Dept. of Water Resources, Folsom has risen 13.3 feet as of midnight last night, from it’s lowest level recorded on midnight Thursday. Here is a link to that reservoir. Click on any title at the top of each list of data and you can see the info in graphical form. Click a second time, and it will let you see the last 4 months in graph. Heavy use today, very slow site. http://cdec.water.ca.gov/cgi-progs/queryDaily?s=FOL&d=&span=1month

  • craig matthews

    Still am wondering if that large area of convection that occurred along the equator west of the date line a week ago contributed to our current atmospheric river set up. That area of convection appears to have fizzled before making it to the dateline.

  • Kamau40

    I think we will see at least a couple more “AR” events similar to this weeks before the end of the rainy season. March should be a wet month for the state incl So. Cal. Also, please read Howard Schectner’s comments on today’s blog on mammothweather.com about what he thinks for late Feb/Mar.

  • Ben

    Has anyone realized just how dry SoCal has been OVERALL in the last couple of years? Think about it- the atmospheric river is not affecting them one bit, they were just as dry as NorCal during this severe drought period for the past 13 months (besides some rare cut-off low events in San Diego), and IN ADDITION- were barely affected by the storms that affected NorCal in November and December 2012. For what it’s worth, SOUTHERN CALIFORNIA HAS NOT EXPERIENCED ONE BIG STORM SINCE THE 2011/12 SEASON. But even that season, I can’t recall anything major but my mind gets fuzzy going that far back. Of course SoCal is dryer than NorCal, but keep in mind that they still should be getting a couple of big storms every year. After all, downtown Los Angeles gets only 5″ less of rain than San Francisco. It’s really not that much less.

    • Dan the Weatherman

      We have not had anything substantial down here the last two years, with some moderate events during 2011-12 especially toward March and April. We are overdue for a good storm down here, and this year has been probably the worst (driest) that I have ever seen to this point.

      To add insult to injury, a warming trend is forecast this week and temperatures are expected to be in the upper 70s to low 80s for much of the week beginning on Tuesday. I don’t want this warm weather and we have had enough of this back in December and January. What I would rather see is a strong series of storms delivering rainfall to Socal like it is supposed to do this time of year! This utter lack of rainfall is beginning to drive me crazy.

      • redlands

        Last good month was December of 2010 – when I recorded over 10 inches of rain in Redlands, Ca for the month of December. — The highlight of this season 2013-2014 is when I recorded 1.03 of rain in November 2013 — one day accounts for about 33% of this entire measly dry season — all other days where I recorded rain were 0.25 and below — like someone on here said — we’ve had nickel and dime storms this whole seasons. It really is a boring rain season. This current rain season looks like it will be my 2nd driest season ive recorded — It really doesn’t appear that we will get much more rain — the season is rapidly coming to an end —- so sad

        • redlands

          I also agree — we have had enough warm weather in Dec/Jan — we have the months of May thru October for hi temps — it could even get hot even sooner — So bring on cold temps rain and snow — Southern California needs some rain — please can u share some rain with us Northern Calif !!!!!

          • CalNative

            It must be said: most people down here detest rain and appear to believe the water that flows through their faucets appears from out of the ether by some sort of magic – no rain required. In news reports, any hint of rain, we’re always assured, will last only a little while and then we can get back to summer temperatures in February. I know Southern California doesn’t depend on local rainfall for its water supply and that rain and snow up north are always good news for us down here, but tell that to the century-old native oaks in my neighborhood that are dropping dead right and left. (And it doesn’t help that everyone in L.A. thinks it is their God-given right to have a garden that looks like it came right out of southern England, down to the green, manicured lawn. For that matter, is it really such a bright idea to grow water-intensive crops like rice in a semi-arid location like the Central Valley?) Sorry for the rant. So frustrated watching the rain blocked above Bakersfield all weekend long and now nothing to look forward to but more baking sun this week. I fear that this is the “new normal,” and we are seeing the beginnings of this part of the state turning into a vast desert, that it will literally never rain again.

          • Loyal Brooks

            For what it is worth, CA is famous for “boom and bust.” which includes droughts and floods. With climate change, we can expect longer and more severe droughts in general. All droughts eventually come to an end, even if the end seems out of view.

          • lurky mclurkerson

            Agreed overall, but in fairness to the rice farmers, flooding of those fields actually provides a huge amount of seasonal wetland habitat for birds on the pacific flyway in fall and spring. The areas where rice is grown now in the Sacramento Valley used to be seasonal wetlands, and that habitat has been whittled down to a tiny fraction of its original area. There are huge chunks of wildlife that rely on those wetlands.

            They do have to hold water on that land longer into summer, of course, than would happen in a natural floodplain, but there are fish and bird benefits from it for much of the year, especially now that they don’t burn off the stubble so much as they used to. Accounting for those tradeoffs doesn’t necessarily make it perfect, but they’re realities I seldom see brought up in the rice-water-usage debates.

          • CalNative

            All interesting and valid points. Given the meagre remains of the central valley’s pristine ecosystem (only 1% of native grasslands remain, as you probably know), I suppose substituting the artificially wet conditions associated with rice farming for the water that used to be there naturally is the most we can hope for at this point. That said, it is somewhat ironic, given that the aquifers, wetlands and vernal pools were destroyed, in part, by human agricultural/livestock practices in the first place.

          • lurky mclurkerson

            Agreed. But the conservation partnership with the rice farmers here in particular over the past 10-15 years is one of the bigger success stories on that front. I don’t know whether water usage will balance out to it still being a great idea here in the long run — the seasonal water distribution matters there — but in terms of groundwork from where we are now, there’s been a lot of serious good work there.

            I don’t know as much about elsewhere in the state, but the vernal pools that remain around here are actually at greatest risk from suburbia-type development — the aglands that still have any are easier to convince to preserve them now than used to be the case. A lot of vernal pool habitats around places like Elk Grove, just south of Sacramento, wound up just barely saved from being covered with tract housing, which is now right on their borders.

            Speaking of, this rain has probably helped them immensely, at least here. Too many dry years in a row will kill off a lot of vernal pool species, some of which really only grow in a couple of pools in some random place in the valley that most people never think about much. Sigh of some relief there, too, even if these rains couldn’t solve everything.

          • Dan the Weatherman

            I hope you are wrong on the possibility that this part of the state may be beginning to turn into a vast desert and that it may not ever rain again, and that instead this is just a dry cycle that we are just going through like many dry cycles of the recent past. If you turn out to be right, then I fear that I am going to have to move from this area sometime in the future in order to enjoy rain once again.

      • It’s been horrible down here. I thought this year would be different. I’m taking a trip to Portland soon and I’m really looking forward to experiencing some weather. At least we had clouds this past weekend. It was better than having weeks and weeks of sun with not a cloud in the sky. I feel like even the marine layer has been less of what it normally is.

        • Dan the Weatherman

          I certainly thought that we would get into a much wetter pattern by mid-late January here in Socal after an extremely dry start and that February would be much wetter overall. With no rain in the forecast for at least the next week to 10 days, then that means that the first half of February will be almost as dry as January, and this is after two awful Februaries and three awful Januaries in a row. We are going to beat 2006-07 for the driest year on record if this continues.

      • Loyal Brooks

        I hear you Dan TW, in CA you have to wait another year if you get a dry one. When I lived out there, that drove me crazy too. Now, it only “bothers” me about what it is doing to the land. Trust me, I know what you’re talking about. Long ago, I used to fish through old records to find a “comparable year” and “set up” hoping that the dice would roll that way again. They almost never do – but that doesn’t mean it won’t!

      • Kamau40

        I do think we will at least temporarily go back to a dry pattern for the next week or so with warmer temperatures. However, the ridge that will be building in will be coming from the mid latitude tropics and it won’t as strong as what we saw during Dec/Jan. I do think we will get more storms and hopefully So.Cal will get in on the action later in Feb/Mar. I was reading this morning and yesterday on Howard’s blog, mammothweather.com, about now the angle of the sun and as the days get longer we should start seeing the back load of the storms, which means we should have a wetter/snowier ending to our rainy season. Bryan Allegretto, on his blogs,opensnow.com is also seeing possible wetter days ahead too in his long range analysis if the ridge sets up in the right place in the Pacific, which affects our downstream weather on the West Coast. I have seen back loaded weather in years past, even during droughts years such as March 1991, 1992 when even So. Cal got hit hard with flooding rains and big snows during the late winters an spring months. The drought won’t end this year, but I do see the possibility of a sizeable dent in this drought which will help to ease the impact of the severe water shortages during the summer/fall months.

        • I hope those predictions come true. This “wet” week has produced .48″of rain in my area, and this is the first rain this season to actually provide some soil moisture, at least at the surface. As someone from So Cal noted, 100+ year old native oaks are starting to die, though not in huge numbers yet. If we can get some late season rain of significance it should help the native flora get through summer and into a hopefully wet El Nino enhanced 2014/2015 rain season. Fingers crossed.

          • Loyal Brooks

            Perhaps it is best those dying oaks burn. Oak trees are among the only broad leaved trees – not including chaparral – that is able to sprout from the root crown. Perhaps it is times like these that they invest in their root crown and not into already grown limbs. Not every sub-specie is able to this, but mysteriously (??) most of the ones in CA can and regularly do sprout the spring after a fire. Like all else, they have a strategy for life.

          • Kamau40

            Yes, I really hoping too that next year will be an epic year. I believe that it will be. I think we have just surpassed the peak of this current drought cycle. We can’t any drier than we have been. Hence, the only way we can go from here is up!

    • Loyal Brooks

      Right, but if a drought were to strike CA, it is most likely to hit S CA the hardest and longest (not always). It’s the latitude and the semi-permanent high pressure the lies off the coast. How else would you get your famed weather? But everyone agrees with you – this is too far.

    • alanstorm

      El Nino to the rescue! Hopefully the predictions hold for next fall. Those juicy El Nino storms usually hit further south. Lots of flash flooding & mudslides as I recall from past events. Keep your fingers crossed.

    • maestra545

      The recipient of so much NorCal water, many urban dwellers in SoCal live in a bubble as far as water use, much less conservation, goes. I read last week that one SoCal TV weather personality said 9% of the state was experiencing drought.

      • Azmordean

        This is overstated. LA has actually done a fairly good job overall in terms of improving conservation. LA’s average rainfall is also not that much lower than SF and is about the same as San Jose (15″). So most of urban California is in a similar boat water wise – all of us who live south of the Golden Gate get much of our water from elsewhere.

        I think your anecdote says more about the brain dead media than anything else!

    • Longbeach90813

      Ben,
      I’m new to this group, I live in Long Beach. Thank you for discussing SoCal’s lack of rain. The last big rain storm I remember was ironically the last “Atmospheric River” we had in December 2010. Downtown LA got over 11 inches of rain in 5 days. I believe that most places north of Santa Barbara missed out completely on that event.
      Well it was our turn to miss out on this last one affecting NorCal. I’m still hoping we can get something big this far south soon.

  • alanstorm

    Hooray for the zonal flowing Pinnapple Express! We got 7″ in 48 hours in Willits. Nice to see the creeks brown and flowing. Saw some actual roads closed from Atascadero creek in Sanoma co. Roads closed under water today. Talk about from famine to feast!

    • Loyal Brooks

      Love it. In a way, it is a little too bad that the water so desperately needed in the soils washed off instead of sinking in. But, in reality, it is always best to “rinse off” the dry accumulations on/in the soils that should have been washing out all along. If serpentine soils are involved, which is toxic and everywhere in CA, it is always best to wash that away from non-toxic soils!

  • Chowpow

    I came home this evening (North East of Nevada City) and checked my rain gauge…filled to the brim, guess I should have emptied it sooner. That’s 10″ at the least.

  • TheNothing
    • Loyal Brooks

      TheNothing, thanks for the before and after pics. These are very useful here!

  • TheNothing
    • snow755

      Is that a creek or lake ?

    • JibJab2

      Cool pics, thanks.

  • TheNothing
  • snow755

    Sonora has pick up 3.51″ twin hart has pick up 4.84″ from Friday two Sunday not bad March needed rain. I want more rain like this one

    In other news. Modesto S totally busted they had all most no rain from this event at all

  • Whyyousoandso

    Been sorting through the comments, but I’m still trying to see what the prediction is for Southern California, long-term. 10-day forecast shows no chance of precipitation.

    • Rains now shift north, and California stays dry (except far north coast) next 7-10+ days. I’ll have more later this week.

      • Whyyousoandso

        Boo…. We NEED rain!

  • Zepp

    I went into town this morning, and it was somewhat surreal. If I had absolutely no idea what the date was, I would have guessed somewhere around Halloween. The air had the scent it has after the first big rain of the season, there were dead pine needles all over the place, and the mountain had a light dusting of snow. The sun was at the right angle. There were even Canada geese migrating.

    So course, these geese were going NORTH…

  • I’ll have an update once it becomes a little clearer what the long-term impact of this weekend’s rain event has been. At the moment, looks pretty dry (though perhaps not completely so) for next 1-2 weeks…

  • Man on Mt. Tam

    Well, we sure did get a big dump. Nice to see the creeks brown and flowing and to rinse some of the debris off the hills and soil. Some flash flooding here and there during high tides, some without power, some flooded basements, and sewers overflowing, but all in all, relatively unscathed, except for the guy that drove off the hill. Yikes! Read more below about the AR’s impact on Mt. Tam and parts of Marin County.

    http://www.marinij.com/marinnews/ci_25104176/mt-tam-gets-21-inches-rain-three-marin

  • Utrex

    Latest cfsv2 is showing much above normal rainfall for north california. Unfortunately for SoCal, it seems that ridge is locked in place.

    http://www.cpc.ncep.noaa.gov/products/people/mchen/CFSv2FCST/monthly/images/CFSv2.NaPrec.20140210.201403.gif

    • I’ve shied away from even mentioning the CFS over the past couple months since it’s been performing pretty badly this year with the persistent ridging. Right now I don’t see a strong signal for CA precip during the next two weeks–just a couple of small/very small events for the northern part of the state. Conflicting signals regarding the possible return of amplified ridging. For now, looks like we’ll see some lower amplitude ridging that nevertheless manages to keep most of the rain away. Also, looks extremely warm in SoCal and across much of the Southwest next 7-10 days…

      • Dan the Weatherman

        Socal is going to earn the nickname of the “Atacama of the North” if this persistent dry pattern continues for much longer. It has almost literally been drier than Phoenix and Las Vegas down here for the last 12 months, which is unbelievable.

        • Dogwood

          Even the tenable regions of the Atacama are drying. Anecdotally, large populations of Copiapoa cacti, once suited to growing there, are becoming stressed and dying out. Many species outside of the fog belt just clinging to scattered ancient adults with no populations of young plants. Not everywhere there, but enough to take serious note.
          I know it won’t take many years to decimate SoCal’s higher elevation pines, cedars, spruce and firs if those mountains get only 3″ in many consecutive years. Really pulling for the whole state to get back on track.

          • Dan the Weatherman

            It must really be getting dry if the Copiopoa are becoming stressed because that is an arid region to begin with. Most cacti in general thrive in dry regions with infrequent doses of water or fog belt conditions except for tropical cacti such as Zygocactus and Epiphyllum.

          • CalNative

            Unfortunately, I believe we may be witnessing the early stages of a catastrophic wave of plant and animal species extinction in the entire Southwest. In geological time, it won’t be long before nearly every aspect of the landscape we think of as “California,” will have vanished. I’m no meteorologist, but I have a sickening feeling that this ain’t no “normal” cyclical drought.

          • Loyal Brooks

            Dogwood, which regions of the Atacama are drying? This is very, very useful information. It can lead to many clues being uncovered.

          • Dogwood

            I should have made this citation, as is customary in such company!
            : ) my bad.
            “Copiapoa In Their Environment”
            Schultz and Kapitany, 2006
            Hardcover ISBN 10: 0646287028
            Mostly field observations of populations under stress. Come at it like a botanist/taxonomist and get the picture of environmental issues as a bonus.
            It’s a depressing book. Pictures of huge dead clumps of formerly glorious cacti.

          • Loyal Brooks

            I don’t think you need to cite everything…but I know how you feel. I am interested in botany too. Scouring my own books and the internet, I know there are about 26 different species within this genus of this cactus, each with its own niche within the desert, and it is difficult to pin down just which ones and where.

            From what I do have, they depend largely on fog drip. If this is what you are talking about, are you suggesting that the fog drip has decreased in some areas? This is more what I was asking about. I otherwise would have to get that book you referenced (that I don’t have).

            If this is the case, then the Humboldt current must be phasing through something. Thanks, Dogwood.

          • Dogwood

            Funny that after I posted I thought I can’t just say ‘oh the Atacama is getting dryer’ without at least a reference, but I let it go. So my citation was a loose end to tie up.
            The book is in storage so I can’t be specific but I’m feeling it’s not the fog that’s disappearing, but actual westward drifting rains over the Andies that are not coming as they once were. The populations that are effected are inland. Canyon and foothill. There seem to be other published explorations that corroborate this. Copiapoa solaris seeds are rarely field collected anymore, for instance. Because they are not flowering. : (

          • Loyal Brooks

            Hey, thanks for the reply! Now I have something to work with here….the eastern side, and I am assuming the northern portion, since that part is what receives the most trans-Andes spillover.

            P.S. You had a very good sentence written here 4 days ago: “Streams of fat low wet looking stratocumulus all day, with no mechanism to make them rain.” Not only is it vivid, it is accurate! Way to go!

  • Thunderstorm

    Looking at the stratosphere charts, the cold weather moves out around the 22nd, over to Europe. What it means for us, guess we’ll find out. New technology so learning cure here.

  • redlands

    Looking at the forecast for San Bernardino/Riverside Valley Forecast — looks like were gonna be in the mid to upper 80’s this week — Oh boy — its too warm — with no rain in sight — so depressing

    • CalNative

      Extremely depressing. At least last week, even though it was difficult
      to accept that we would be missing out on all the rain that was falling
      up north, at least it “looked” and felt like February here, with cooler
      temperatures and cloudy skies. Now, to have to endure a string of dry, 80º+
      days while the clock runs out on what’s left of the so-called “rainy
      season” is truly rubbing salt in the wounds.

  • Dan the Weatherman

    I have been reading local AFDs indicating that this upper ridge that is now beginning to dominate Socal is subtropical in orgin, as opposed to the RRR that was high-latitude extending down to the mid-latitudes. Is this by any chance the Hadley Cell displaced northward of its typical location for this time of year, or a larger than normal version of it? I know that the Hadley Cells are large subtropical high pressure systems located approximately 30 degrees latitude both in the Northern and Southern Hemispheres.

    • Loyal Brooks

      Dan TW, I am beginning to suspect that there was no single RRR after all – only by appearances. By sheer fluid dynamics, the extended life of that mid-latitude ridge should have been repeatedly undercut and broken down over and over. This is the usual mode of the atmosphere. I am beginning to realize that two separate ridges joined forces to create a “Super Ridge.” The ONLY REASON the mid-latitude ridge was able to anchor itself so firmly was that it was not ever undercut – not even once (I should check the records on this) – but the general thought is here. That would allow the energy found in the Hadley Cell (the zonal area around the world between 20-40 both N and S, where nearly all of the world’s deserts are) to extend northward and help support the anomalous ridge.

      I am beginning to see (I always suspected, but had no way of proving) that this extreme anomalous ridge was not just a single ridge, but actually two separate phenomena that linked up.

      • Loyal Brooks

        Global warming plays a role in the above, but perhaps not what it might seem. Global warming is very uneven, heavily concentrated in high latitudes, to almost none near the equator.

        So, in the thought presented above, it is not so much about the Hadley Cells growing – they probably aren’t. They may sway in strength from year to year and place to place due to the teleconnections (i.e. climatic oscillations over a whole ocean basin, for instance), but overall, that is not where the focus of global warming affecting the earth’s climate. It is in the mid to high latitudes.

        The arctic regions are warming most rapidly, which encourages ridges from mid-latitudes to be drawn farther north than usual. But due to the facts of fluid dynamics, all mid-latitude ridges come to an end (one favorite way to come to an end is to be undercut by the jet stream).

        If the ridge is “anchored” to the Hadley Cell (or another node of oscillation of high pressure aloft), it can and will become a Super Ridge.

        • Dan the Weatherman

          I think you are right in that there were two ridges, the subtropical ridge (Hadley Cell), and a larger than normal mid-high latitude ridge (the RRR) that covered the Gulf of AK and the eastern Pacific extending down to the CA coast. The two likely formed a monster ridge extending from the subtropics to Alaska, that completely blocked the jet stream and its associated storm track from reaching the west coast in December and January, and forced the jet into AK instead. I think the lack of MJO activity was in part responsible for holding the pattern in place for so long, and the MJO is still weak as of right now. I am also thinking there is the possibility that all the industrial pollution from Asia, especially China may be modifying the pattern in the north Pacific and that may be contributing to the dominant nature of the RRR lately. This may also be a contributor to the warming in the high latitude regions that has been more prevalent in recent years.

          • Loyal Brooks

            The Hadley cell isn’t really a ridge, but a zone of high pressure that encircles the globe at around 30 deg lat, N or S. There are areas, due to the configuration of land and sea, where the Hadley zone cannot set up shop. (Example: Monsoon areas of South Asia). Otherwise, deserts form at those latitudes.

            This zone of high pressure follows the sun through the seasons. As the overhead sun at 90 degrees moves N and approaches 23 deg. N, so too does the Hadley cell move N, staying about 20 degrees latitude N of it. This provides CA with abundant sunshine during the summer. Since it remains offshore, it is unable to totally keep out moisture from occasionally creeping up from the S or SE and into CA.

            During the winter months, the opposite is true for us. The Hadley cell retreats southward (following the most intense sunlight) and allows GOA storms and fronts to enter CA.

  • snow755
  • Ian Alan

    Haven’t posted in a bit, the new format ie disqus wasn’t pleasing to me, but I’ve submitted to it – lol – so as to participate in conversation and report results from my area – San Bernardino mountains @ 6200′ ASL. Redlands, I’m the guy right above you in the mountains.

    An average season will produce aprox 12 feet snow plus around 30″ rainfall. 12/13 we topped out at less than 6 feet snow with aprox 10″ rain. 13/14 we have less than 6″ rain and barely a foot of snow. Sad, very sad. The warm and dry end of December and all of January gave way to budding willow trees, daffodils sprouting and various small plants that regrow each year from roots.

    The last heavy rain season, was it 03/04? Many mountain locations recorded 130″ plus rainfall – jan, February, mar each recording 30″ or more.

    The heavy rains December 09, or was it 10? Mountain locations from lyttle creek to crestline, lake arrowhead and running springs all recorded 28″ upwards to 48″ rain in a 7 day period. My location received nonstop rain and topped out at 42″, 3 days in a row each had 10″+

    It’s not uncommon to have 3 foot snowstorms and back to back storms that produce 5 to 6 feet in a matter of days. Hence what may seem like high average snowfall for SoCal to some not familiar with the mountain climate and huge difference orographic enhancement can make. The bulk of our snow/rain comes in 3 or 4 large storms each year.

    Just thought I’d give an overview of the type of weather I’ve become accustomed to and how dreadfully boring this winter and last winter has been!

    The first rains we recently had about 10 days ago or so gave me just over 2″ rain and sadly that is equal to the last highest rainfall this year back in October. :/

    • craig matthews

      I’m from the central coast big sur area and I remember reading about 100+inches of rain in lytle creek in the winter of 2004-05. Its amazing how those mountains trap those rainclouds and wring so much rain out of them. This has been the most boring winter of all time so far and we are so overdue for action. seams like we get more action from the summer monsoon these days. I was up at arrowhead in somewhere around 2001 or 2002 and remember seeing all the dying pines. Having these record dry winters so close together is really taking its toll. We are starting to see the landscape change before our very eyes. In my area some old growth redwoods have died in the last 6 months along with many small oaks and brush types. This is very scary having lived in this area for 40 years and talking to old timers who have never seen anything like this. We just received our first significant storm here with a storm total of 4.17 inches which is the most since the storms of nov/dec 2012. But these storms are not getting down into socal like they use to. Hope this changes soon or we area going to see some real permanent damage to the landscape.

      • Dan the Weatherman

        I am hoping this changes really soon and that we aren’t permanently headed into a drier climate. Next year absolutely has to NOT be ENSO neutral or weak ENSO either way with the current -PDO and +AMO. We need a moderate to strong ENSO event, whether it be a La Nina or an El Nino for drought relief in the near term. For longer term relief, we need the AMO to go negative and/or the PDO to go positive.

        • Loyal Brooks

          Dan TW – you are on to quite a bit here! I have a question to lob at you…what do you make of the fact that none of your teleconnections/oscillations (ENSO/PDO/AMO et al.) have flipped or changed in the last month, yet there is a profound change in the general circulation not only of the N Pacific, but of the whole hemisphere? Here in MN, the weather has gone from night and day in 36 hours, and is expected to stay this way for a while. Changes are occurring across the Atlantic and over Europe, as well. No index has changed. How do you account for that?

          • Dan the Weatherman

            A couple of shorter term oscillations changed sign at the beginning of February, with the AO shifting from negative to positive and the PNA going negative after being positive. The shift to -PNA has helped to change the pattern that brought the recent rains to Norcal, +PNA is associated with west coast ridging, while -PNA usually favors a west coast trough. There may be some other factors that I am not aware of that changed as well.

          • Loyal Brooks

            You think more in terms of climate than weather. Those teleconnections are climatic factors. For me, it is split down the middle very evenly.

            There really is nothing like a Midwest T-Storm. The sky is continuously lit by lightning for hours, yet gets so dark during the day that streetlights go on. To see the black clouds above you quickly move to the S looking west, and to the N looking east, with a blast of wind approaching 70+ mph lets you know the storm has commenced. The 1″ hail shreds leaves – get your car into the garage!! Now THAT is weather!!

      • Loyal Brooks

        As bad as the drought is and as much toll it is taking on the forests – it would seem hopelessly depressing.

        I have found one curious thing that helps me “through times like this.” There are scattered knobcone and coulter pine around 2.000′ in Baja about 100 mi. S. of San Diego. The weather records there show 1 year in 10 – ON AVERAGE – receives no significant rainfall. Average is around 5.” Yet, there they are. They do sit in the marine layer though.

        However, just go S and inland to about 8,500’+ and look at Jeffrey, lodgepole, western white pines, (and even incense cedar) in places. All of these trees are adapted to severe drought – for a living! Weather records for that area are extremely hard to come by, so by extrapolation, these forests exist on perhaps 20-25 inches, with only a few inches/ year occurring on a regular basis. You can see what I’m talking about on Google Maps. See areas around San Pedro Martir, around 90 mi. SE of Ensenada.

    • Dan the Weatherman

      Alan, it is good to see you back here on the blog! I was wondering if you were going to post again at some point, but I figured that you were taking a break from posting because the weather has been so boring lately.

      • Ian Alan

        Its hard to talk about boring weather isn’t it! How many ways can ya slice that cake?

        Snowfall was just below average, which is saying something considering I had 60 some inches of rain total for the season on top of ten feet or so of snow (would have to double check the exact totals but within that range)

        The December 2010 deluge – we were right on the cusp of snow almost the entire time, with many instances of hail/sleet and snow mixing in – the San Gorgonio peaks above 10k, of which there are quite a few, my god could you imagine the snow equivalent?!? There are a few that braved the storm to witness it and it is confirmed that the snow level was below 10k, often fluctuating from 8k to 9k.

        20+ feet of snow easily in a 7 day period, nuts!

        Craig – the 03 and 07 fires, the dry weather and the pesky bark beetle are not kind to these forests, yes sadly they are visibly disappearing.

    • Kamau40

      Hi Alan,
      I used to live in San Bernadino Co with my father and mother when I was a kid back in the early 80s. I’ m very familiar with the beautiful San Bernadino Mtns. I’ve been to Lake Arrowhead and Big Bear many times. The avg numbers in terms of rain and snow you’ve mentioned above, from my memory, is very accurate. Although back in the 80s, I think is was a little bit more, at least 15′ of snow with 20″ or so of rainfall. We had big time gully washers between 1981-83, which were actually some of our wettest years of the century and on record. I’m curious to know, how low is Lake Arrowhead currently?

      • Loyal Brooks

        And almost no one east of the CA line has ever heard of this very unique, intensely orographic area, let alone such an area exists in S. CA. Perhaps CA is an island in too many ways?

        • Dan the Weatherman

          Both the San Gabriel and the San Bernardino Mountains have peaks over 10,000 feet in elevation. When the flow is just right (usually southerly) orographic lifting can bring incredible amounts of rain and snow to the windward facing mountain areas.

          • Loyal Brooks

            Yes, And in total and complete agreement on this, no one from my graduate Meteorological school (Penn State) even acknowledged that there was anything at all interesting or curious about weather of any sort west of the Rockies, specifically CA. That irked me as I quietly knew of these things while they did not.

            All that mattered was the next nor’easter. Weather-wise, NOTHING in CA matters. After a certain point, one needs to get away from that in a professional sense.

          • Dan the Weatherman

            Socal is about the only region of the country in which you could go skiing in the local mountains and then go to the beach and surf on the same day.

            There are many microclimates in Socal. The lowlands are Mediterranean and the closer to the coast, the more marine influence there is. The lower hills are chaparral, which consists of native oaks and various types of coastal scrub and sagebrush. The higher mountains are less Mediterranean and more temperate to some extent and consist of pine trees such as Jeffrey and Coulter pines along with possibly some broadleaf deciduous trees, and they receive snow during the winter months. Then, of course are the true desert regions such as Palm Springs and Lancaster, which have the driest climate. California fan palms (Washingtonia filifera) and Joshua trees (Yucca brevifolia) are native here.

          • Loyal Brooks

            Yes, yes, that is basically why I enjoy the Mediterranean climate superimposed over complex terrain. The resultant amazing array of landscapes, to me, is CA’s greatest asset. I call the trees out by name, just as you do.

            I can’t wait until I get back out there! Here, it is beautiful but monotonous for hundreds of miles in any direction (except the Great Lakes). The UP of MI is one other place sort of like CA.

      • Ian Alan

        Did you ever get back in to explore Deep Creek? I just have recently and found the large cliffs and deep swimming holes – its worth noting how much colder the canyons are than for example the ridge top my home sits on – 54F when I left my house, 29F in the canyon with frozen creek you can easily walk over, snow still powdery from more than 3 weeks prior.

        I can’t explain why, but Lake Arrowhead is at the same level it was at the end of summer, which is only maybe 5 feet below being full, nothing out of normal for end of summer / early fall….it certainly would have been full at this point during any normal winter though.

        Drove by Lake Cachuma this morning and that is the area I grew up in, never has it been this low since the 80’s anyways….at least 20feet down, quite a sight!

  • craig matthews

    I still am holding on to my belief that the RRR is gone. Now we are dealing with a more typical -PDO/+AMO ENSO neutral pattern, which to me looks kind of similar to a la nina winter, where the pacific northwest and norcal are wet and the desert sw and socal is dry. The pattern has changed but socal is still not being favored as that stubborn low amplitude ridge sits between pt conception and Hawaii. I think this ridge is the reason why the RRR never got undercut so far this winter. Because there were several times when the RRR was up in Alaska and there was plenty of room for the pacific jet to undercut the ridge, but because of this low amplitude ridge off socal I think it kept the pacific jet from punching through to the coast. But one thing we can count on is that there are always exceptions to our rules. And there is still a chance socal could get some good storms between now and april, or even may. Some of the latest models are showing a ridge building northwest of Hawaii toward the aleutions after this next week, which would cause a trough to dig down from the gulf of Alaska into the west coast. A trough digging down the coast would at least give socal some rain. And if the position of the trough is just right it could give us some good rains even if the trough is from the northwest. We had several troughs from the northwest in late 2011-12 season which brought some very good rains in late march-april of 2012. So its possible. Not writing this winter off just yet.

    • Dan the Weatherman

      I think this low latitude ridge may be the reason why the RRR wasn’t able to be undercut earlier on. If this is the case, that means there has been wall to wall ridging from the subtropics to the polar region in the eastern Pacific, which would explain why all the storms were going all the way up into Alaska before coming back down over Canada and into the Midwest and east.

      • Loyal Brooks

        It almost seems that the RRR wasn’t a function of a single ridge at all – just the outcome appeared to be so. It seems to be that the low-latitude ridge stuck between Baja and Hawaii has been unusually firmly anchored this year (which prevented undercutting by the jet stream). This, together with the mid-latitude anomalous ridging over the west coast, allowed the drought to spread northward out of CA and into BC.

        The recent reconfiguration of the jet stream across the N Pacific, doesn’t seem to have affected the low latitude areas. For CA, the progressive pattern in the Pacific seems to want to stay N of 40N. South of that, there is increasing influence of this separate, low-latitude area of high pressure. In the models, when a trough seems to be able to break south of 40N, it is too close to land to be of much help with providing precipitation – inside sliders.

        Thoughts on this??

    • alanstorm

      What about the stuck north-south Rossby wave jetatream orientation that was going on during the reign of the RRR? Surely that was the main factor in its longivity

      • craig matthews

        I agree with you there too but at times this winter I have noticed that the RRR appears to split into two centers, one in the Gulf of Alaska and the other off socal. Then at times the two centers merge as one giant center over the entire eastern pacific. Right now the southern high center remains as a deep low is now in the gulf of Alaska, which seams to be holding that atmospheric river over norcal and not allowing it to drop south of the bay area.

  • lightning10

    I am interested in that cold solution as well. Models might be onto something.

  • Dan the Weatherman

    I am really surprised the local NWS offices (San Diego and Los Angeles) have not been emphasizing the extreme dryness in their AFDs as much as I would think they would be doing at this point.

    • lightning10

      I feel you Dan. This season has been a moral killer. 2 reasons this season sticks so much in my opinion is

      1. The expectation was low for most people to start with. The last time people where this confident that the season was going to be poor was right after the El Nino in 1998.

      2. Most people don’t care that its been a bad winter. Most people I talk to they enjoy it and say “Boy we are lucky not to live (list your favorite East Coast city)

      It might be best if you have decent transportation/funds is to join the growing amount of people who go storm chasing during the monsoon to fill the void.

      Even that is risky as the monsoon has been average at best with a few exceptions.

      • Loyal Brooks

        At meeting yesterday to hear report from one guy who went to San Diego last week for a national convention. He said it was “chilly” out there as a joke. It is already understood to be virtually rainless.

        The rain in N CA is causing quite a changeup in MN, and it should warm up from continuously near or below zero for weeks – to a shot at crossing the thawing line for a few hours for 2 or 3 days later in the week. Of course, it always warms up for heavy snow.

  • saw1979

    I happened to stumble across this blog while looking for weather news last month. I know next to nothing about weather forecasting and looking at climate maps, but have really enjoyed the information and comments here. I’m in the Central Valley and we had our first foggy day of the year today. Usually we have weeks of fog in December and January…but I’m guessing that didn’t happen because there was no moisture in the air. It was nice to wake up to!

    • Dan the Weatherman

      I believe you are right that there has been very little tule fog this year due to a lack of precipitation that has resulted in very dry air. It seems when I have checked some of the observations such as Bakersfield this season, the dew points have been very low.

    • Loyal Brooks

      It usually takes soil moisture to provide the high dew points needed for valley fog development. It is estimated that fog forms after the first 3/4 inch falls within a few days, which is usually long before now!

    • Xerophobe

      I’ve learned a lot here, too and the reports from those participating in the discussion.

    • lurky mclurkerson

      Loved it here, too. I’d almost forgotten how much I enjoy our tule fog (especially when I don’t have to drive in it much, though I secretly always think it’s kind of fun in a hazardous sort of a way.)

      Last night got foggy, too, in the wee hours — I was up with insomnia and got to see it — but it had largely cleared out of urban Sacramento by sunrise. We don’t get the thickest stuff in the city here, but I grew up around the delta, where we didn’t have “snow days” at school because instead we had “fog days.” Amazing stuff.

      And yeah, a winter with next to no fog is strange. The air (and the ground) has all been so incredibly dry up until recently, almost like a desert climate — warm, dry days and cold, clear nights.

  • TheNothing

    For the last three hours Folsom lake has been releasing almost as much water as is flowing in. I don’t understand this.
    http://cdec.water.ca.gov/cgi-progs/queryF?FOL

    • Looks like a short pulse of releases probably aimed at flushing downstream regions for environmental/water quality reasons. Looks like they’ve already closed the gates again…

      • Loyal Brooks

        Mandatory environmental law and water quality reasons. There are current heated congressional battles over this – not appropriate here.

        • lurky mclurkerson

          Given what the lower American River through urban Sacramento has been looking like for the last months, I can’t say I’m surprised, nor that I blame them in the least regardless of the rest of the political stuff (which I ain’t touching with a ten mile pole.) Water quality through here has been going pretty sour very quickly.

          Seriously, there are places where you could practically just hop across the lower American on riffles, in mid January. I’ve never seen it so low as it has been this winter. Places downstream of Folsom largely take their water directly from the river (and put their treated wastewater right into it, which requires enough flow to water it down and not just be gross.)

          • Loyal Brooks

            I imagine you are correct in what you surmise. The current law is to use water to flush out not only what you’ve mentioned, but to keep fresh(er) water running thru the Delta for the salmon runs and such.

            I actually happened across C-Span last Friday that involved a vigorous fight over the right of N CA to allow water to be “wasted” to the Delta and sea. “There are no fish more important than people” was a refrain from the business/money side – “that water belongs in the SJV and S. coastal cities.”

            I will post this here only b/c it is germane to the question of why dams are releasing water at this time, and that it DOES have political consequences. That will be all.

          • Travis Mason-Bushman

            And I’ll only note that there are a whole lot of people whose jobs depend on the presence of those fish – making the argument disingenous at best.

            It’s not a question of “fish are more important than people,” it’s a question of whether SoCal urban districts and SJV irrigated agriculture are more important than NorCal commercial/sport fishing.

    • Xerophobe

      Did you know the dam is getting new flood gates installed? And here’s a recent article and the video is worth the time.

      http://www.news10.net/story/news/local/2014/02/04/folsom-lake-water-management-questions/5214551/

  • Dreamer

    My prediction: LA and San Diego area will not see another single drop of rain until next fall. The next rain event in LA will be on November 20, 2014 and the downtown weather station will pick up a whopping 0.08 inches. All the media will go into stormwatch mode and everyone will whine and cry about how much the hate the rain and want their sun back even though they literally haven’t seen a drop in almost 10 months. Anyone else want to predict Southern California’s next rain event?

    • Cliff Collipriest

      Please be wrong. I need rain THIS winter to keep from going nuts.

  • alanstorm

    Well that lovely Pinapple Express AR is still funneling moisture like a firehose to the NW Ca & Oregon coast. Just as I thought- we had a “stagnant” pattern of high pressure for 13 months, now it looks stuck on a new “stagnant” regime of subtropical zonal flow. They need it, as they are in a drought as well. The rain-line is just north of me (Willits/Ukiah) but soon it will be sagging south. I think this fetch of warm moisture shoumld eventually hit everyone in Ca at some point. This kind of zonal flowing AR, esoecially if combined with a really cold Gulf of Alaska low, may even produce river flooding wherever its aimed at. By the end of Feb we should all be very wet & soggy.
    Just what the doctor ordered!

    • If you’re south of Ukiah, I would not count on very much precip over the next couple of weeks. You’ll get something, but I doubt it will amount to more than 50-75% of normal for the period.

  • sc100

    It looks like February precip will probably end up around normal for most of Norcal. So not a Fantastic February but at least things are less catastrophic with the water situation. Things still look absolutely horrible for the southern half of the state.

  • eric

    local weather says rain chance next wed. here in los angeles. At least theres hope

  • My goal is to have a new blog update tonight. Looks like there will be occasional rain over the next week over the north, focused mostly on the far north near the OR border. Rainfall will be light in the Bay Area/Sac region and nonexistent further south. After that…looks like we may be entering another extended dry period heading towards the end of February. More later…

    • Kamau40

      Took a peak at some of the long range models which seems to be hinting at another extended dry period by the end of the month into at least the first week of Mar. Makes me nervous again. That is the last thing we need. We are still well below normal with the state’s precipitation levels and we are not too far off with the start of the dry season. Which makes me nervous about the upcoming new dry pattern. Historically, around mid March, the main storm track starts retreating north again which is where it has been pretty much all year with the exception to last week. It is another reason why I don’t believe we are out of the woods in regards to the current drought, but perhaps with last weeks rain/snow it has helped to ease somewhat the drought’s impacts.

      • craig matthews

        If the RRR redevelops in the next two weeks, that would be absolutely insane. I just can’t believe it can continue on like this for much longer. Somethings got to give here.

      • lurky mclurkerson

        To agree and echo and put an exclamation mark on it:

        Out of sheer curiosity, I did a full 3 year plot of DWR data for Folsom Lake storage. This is in acre feet, daily, from yesterday.

        Though that last storm did help, we still need serious precip to even reach the _low points_ of the last several winters.

        I haven’t looked at the other major reservoirs’ longer term data, but I suspect they’re pretty similar, overall.

  • Dan the Weatherman

    I just would like to know what it is that is so different this year than all the years since 1877-78 that is causing an almost rainless winter for Socal. It is not that dry years are not normal, they definitely are, but to go through this long in the season with only 1.20″ for the year in Los Angeles and possibly dry on through the beginning of March is absolutely ridiculous. Something is going to give at some point.

    • craig matthews

      So would I. The fact we are getting record dry winters so close together like this is scary. Examples; 2001-02, 2006-07, and present.

      • Dan the Weatherman

        Los Angeles has recorded less than 7″ for the season three times already since 2000: 2001-02, 2006-07, and 2012-13. The entire 20th century, on the other hand, had only three years with less than 7″ in Los Angeles: 1923-24, 1958-59, and 1960-61. This is a bad trend going into this century and I hope it is not a sign that we are on our way into a megadrought pattern.

    • craig matthews

      We have gone into such an extreme that we cant even compare this winter to any other winter on record. And our records go back only so far. This has probably happened before at some time way past. But to not get one good storm in a whole season is very strange. And if we don’t get a good storm in the next few months then I’m saying there is something very wrong here.

      • CalNative

        “Something very wrong here.” “This is scary.” “Strangest winter I have ever seen.” What is the “elephant in the room” that these phrases seem to hint at yet dance around? Has the global climate changed so much, so quickly, that Southern California is evolving into a desert region before our eyes? Underneath my sadness that hardly any rain has fallen this “rainy season” here is the gnawing anxiety that it won’t fall next season or the next, or…well, ever again, really, and that this unprecedented, “strangest winter” is the new normal.

        • Dan the Weatherman

          We won’t know the answer for another few years at least. We need to see the AMO go negative again at some point and the PDO to positive again in the future, for example. We need to see how future years play out precip-wise with different conditions other than -PDO, +AMO, ENSO neutral or weak ENSO, which is, by the way, the driest combination of all for Socal that I can think of and is the regime we are currently experiencing. If we have another very strong El Nino 1997-98 style combined with a +PDO sometime in the future and Socal goes almost rainless for that season, then it is certain that the global climate has changed considerably.

  • craig matthews

    In regards to my earlier comment about the RRR not being undercut this winter. I’m not claiming to be right about this, but just noting what I have observed over the period between November and January of this winter. And that it appears at times that the RRR splits into 2 centers, one in the gulf of Alaska and the other between socal and Hawaii. And then when these two centers exists the southern one becomes dominant sending whatever energy is allowed under the northern center up into the pacific nw and norcal. And other times these two centers appeared to join as one big center over the entire ne pacific. And even more frustrating is the impeccable timing of the ridge that seams to keep redeveloping between socal and Hawaii just at the perfect time when the RRR breaks down and where the entire state could be getting storms if it wasn’t for that low amplitude ridge.

  • Latest model runs seem to be (strongly) hinting at a return of high-amplitude ridging off the West Coast during the second half of February. Is the RRR dead? That largely depends on how one defines it, but it’s starting to look like the reign of extremely anomalous flow over our region might not be over yet. New post late tonight.

    • Kamau40

      Dan,
      I think you are right, this has been the strangest winter I have ever seen. I’ve lived in both So. Cal and mostly Nor Cal all of my life. I have lived through droughts and floods here in the state. Yes, dry years and wet cycles are indeed normal for a Mediterranean climate like ours. But, I never seen when we thought we are finally see a change in the weather pattern like last week with flooding rains and now all of a sudden looks like we are going bone dry again?? What is more interesting is the wet flow did not reach So. Cal which is very strange. Hence, in years past both Nor Cal/So Cal would get hit hard even after a mid winter dry spell. Furthermore, usually when a dry pattern breaks, it would last for awhile even for the rest of a season. That has always been the case in years past, but not this year. I do think that there is something not right with this whole weather pattern, but there is no silver bullet to explain it. It will take years of research before a possible answer will come about. Also, while I think next year will “possibly” be an epic year, we still have to be cautiously optimistic, because we don’t know for sure. So far, most of the models are pointing to a major El Nino later this year which gives me hope. But, remember, not all moderate-strong El Nino’s guarantee heavy rain/snow for Ca, it just increases the odds. The same is true for strong La Nina events which does not guarantee a dry winter for the state, it just increases the odds such as the case for 2010-11.

  • Dan the Weatherman

    The first line of this afternoon’s San Diego AFD reads:

    HIGH PRESSURE ALOFT WILL BRING DRY AND PLEASANT WEATHER THROUGH SATURDAY.

    This weather is anything but pleasant especially considering we have had hardly any rainfall to speak of this winter and are running huge rainfall deficits, and all the hills are brown and ugly as opposed to greening up like they should be by this time of year.

  • mycoholic

    I am not liking what I have been seeing in the models the past few days. I kept thinking that maybe the forecast for next week’s low pressure system might show it growing bigger and sticking around longer the closer we crept toward the 20th, but it seems the opposite is happening. And the forecast thereafter looks terrible. I sure hope the models are wrong……

  • rainscout

    I will throw my hat in the ring for the “strangest winter I have ever seen”..today in the Santa Cruz Mtns. was like late May early June..warm and dry??!! Does not bode well for rainfall chances…so far we have had one weather event this whole winter..we were on the Southern edge of the last event and “orographically sucked in 5″…great to see if it was the start to a wetter regime..but I dare not hold my breath too long as that high pressure is still around…almost seems surreal…like the Socchi olympics at 60 plus degrees..what is going on??!!

    • alanstorm

      Hang in their Rainscout, you might get something Saturday night.- Half inch of rain? Better then nothing. Can’t imagine SC mountains & rainforrest-like places like Zayante being bone dry in Feb! Lived there in the 90’s El Nino years. Winters there are WET, mudslides & raging streams for months at a time every year.

      • TheNothing

        I think a half inch is a little overly optimistic.

  • Update in progress right now…will be posted late tonight.

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