California has experienced a long March quiescent period over the past couple of weeks–not at all an unusual occurrence. Over the coming week, the strong ridge over the West Coast will begin to break down and increasingly unsettled weather will begin to overspread much or all of the state by early next week.
By Wednesday night, a trough of low pressure will begin to approach the California coast. Though this system is not a strong one by any means, it does have a fair bit of moisture associated with it, and a considerable amount of cold air aloft. As result, some locally heavy showers (and perhaps an isolated thunderstorm) will be possible as far south as the Bay Area into Thursday.
After the weak Thursday system, skies will clear and temperatures will warm going into the weekend. Highs in NorCal will be back in the 70s and highs in SoCal will rise back into the 80s. This warm spell, however, will be very short-lived. By late Sunday, a much stronger storm system–this time driven by a strong meridional jet stream–will slam into California. Current model runs do indicate the potential for a pretty substantial early-spring storm, with possible strong winds, heavy precipitation, and (of course) the potential for convection. This is a way out still, but both the GFS and ECMWF have shown for several days the potential of a major pattern change during the first week of April.
Subsequent systems, all slated for the midweek period, will probably follow a track favorable for rainfall statewide, including Southern California. Given the time of year and the relatively cold origins of these systems, convection will likely be significant issue at times next week. All in all, it does appear that the wet season is not over yet in California. Stay tuned!
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