Weather headlines:
-An early-season low-pressure system moves over California through Friday.
-A cool air mass will remain in place through Friday, but turn more showery tonight.
-While not every location will see showers and thunderstorms, any shower activity will be capable of producing heavy rainfall, especially across the interior portions of Ventura, Santa Barbara, and San Luis Obispo counties through this evening.
-Some showers or thunderstorms could linger into Friday before the low-pressure area and the associated air mass exits California.
-A warming and drying trend should develop over the weekend and into early next week.
Detailed forecast:
The latest satellite imagery shows a vigorous early season trough just off the Central Coast early this morning.
This trough will wobble around the Point Conception area Thursday afternoon while digging slowly southeast.
Shower activity has already developed across the interior of San Luis Obispo County this morning.
Shower and thunderstorm activity should become more expansive as the day progresses and daytime heating steepens lapse rates and destabilizes the atmosphere.
Models have indicated the highest probability of rain across the interior portions of San Luis Obispo, Santa Barbara, and Ventura Counties this afternoon and tonight.
A flood watch remains in effect until 11 p.m. tonight for the interior portions of Ventura, Santa Barbara, and San Luis Obispo counties.
Low clouds and fog are filling in across the southern California bight and Santa Barbara Channel, but low confidence exists in the cloud forecast as middle and high-level clouds streaming over the region are disrupting the marine layer stratus formation.
Where there are clouds, the instability with the trough will likely produce patchy drizzle this morning as the instability interacts with the deep marine layer depth in place.
Clouds should continue to fill in across the Southland as the trough position should promote low-level moisture to increase.
A cooler air mass will remain in place for the next couple of days as the trough slowly drifts southeast across the area. Temps are expected to be cooler closer to the coast compared to inland communities.
A drying and warming trend should begin on Saturday as high-pressure aloft starts to build into the region.
Some low clouds and fog could remain across the region, but less low cloud coverage should be expected into the weekend.
Have a great day, Central Coast!
