Well, today’s weather was certainly not what it had been expected to be across Southern California. There were (and still are) a few lines of strong thunderstorms approaching severe limits over the coastal waters, but not to the extent that might have been expected given the powerful large-scale forcing and dynamic instability present (the Severe Thunderstorm Watch, it seems, did not verify). There was one particularly strong cell that brought down trees and power lines in the Hanford area in the San Joaquin Valley, but there were no other reports of significant damage from these storms. The tropical plume, too, was not particularly impressive, as much of it was shunted to the east over AZ and Baja CA. Some heavy rainfall totals did occur, but they were fairly sporadic and not of the magnitude that had been forecasted. The models performed extremely poorly with this past series of storms, though that is not entirely suprising given the complexity of the pattern.
While all this “excitement” was going on in the south today, a very cold airmass began to inch southward down the far N. CA coast. Precipitation began in Eureka as rain, but quicky changed over to moderate snow at the beach as temperatures dropped rapidly into the mid 30s by mid-afternoon. I don’t expect sea-level snow to occur much further south than the Mendocino coast, but it’s something to keep an eye on. Cold and unstable air will overspread NorCal tonight, bringing showers and eventually very low snow levels (sea level to 1000 feet in the far north, 500-1500 feet as far south as the Bay Area, and 2500-3500 feet on the Central Coast). Showers will taper off later on Monday before increasing again on Tuesday. Weak to moderate disturbances originating over the Gulf of Alaska will being chances for showers to NorCal and possibly SoCal every 36 hours or so for the next week, with snow levels dropping below 2000 feet with each wave. No particularly heavy precip in sight, however. The outside chance of some local snow in valleys in the Bay Area and the Sacramento area is worth watching this week, but not likely.