It is not uncommon to see temperature swings on the Central Coast in late April and into May, but to see the potential for a multi-day rain event in May is somewhat compelling.
First thing first, let’s tackle the short-term forecast. Right now, there are some low clouds at the beaches and near coastal valleys but developing and strengthening offshore winds tonight should actually push some of that cloud cover back, it might only work partially into Wednesday, but a larger retreat of low clouds is likely Thursday.
The exception would be the Southcoast where some eddy circulation between the Southcoast and the SoCal bight could bring occasional low clouds to the Southcoast.
For the Central Coast, the offshore flow is night and morning hours, and not particularly strong so the warmest temps may take place in the early afternoon before fading in the afternoon when the land mass warms up producing the sympathetic sea breeze.
Inland the offshore flow is not the source of the warmth, it is the high-pressure ridge causing the marine air to be too low to influence the interior. In fact, Wednesday could already see temps near 90 and subsequent days make that more likely.
Not a lot of day-to-day chance Thursday into Sunday as the ridge peaks over the area. It is after that that things could get quite interesting. A trough of cold low pressure looks to dig into The West. The cool air starts arriving Monday and models have been showing shower potential as early as Tuesday with some models showing a multi-day shower event Tuesday into Friday in Central and SoCal. It is a bit early to make a meal out of all of that but cool and unsettled with some showers certainly looks like a good call for next week.
Beyond the 6th models start to diverge quite a bit but I think it is probably wise to follow the Climate Prediction Center’s outlook for the 8-14 day which continues to call for cold and unsettled potential.