Summer for a few more days, then winter again?

Not much time for a full update this evening, but here’s the synopsis:

After cooler weather today, the high pressure offshore will build back in between now and the first part of the weekend, bringing 80s and 90s SoCal and 70s and 80s in NorCal once again. Record-breaking heat will be somewhat less likely/widespread that it was 2 days ago, however. It does appear that a Pacific storm will approach the CA coast from the NW by the middle of next week…for the first time in quite a while. The system is not going to be strong, but it may have the potential to bring some interesting weather to parts of the state. Given the rather sharp nature of the trough (which may pinch off briefly into a cutoff low as it moves over CA), strong daytime heating could occur in the north ahead of the front. This insolation from the strong late-March sun and the increasing moisture and dynamics ahead of the main system could potentially give rise to some rather unusual prefrontal convection in NorCal. This may be confined to the higher terrain north of Mendocino, or could extend to all elevations as far south as the Bay Area or even further south. There’s still a lot uncertainty in this regard, but a chance of some strong thunderstorms on Tuesday exists, esp. in the far northern part of the state. 850 mb temps tunble behind the front from nearly 20 C this weekend to 0 C by Tuesday…possibly initiating some more widespread convection through very steep lapse rates (and perhaps even a bit of snow down to 3000 feet in the far north). Rainfall with this system will generally be light, but it will be worth watching over the next few days. In the meantime, enjoy our preview of a long, hot, dry summer to come…