Cooling trend with chance of rain through Friday
A cooling trend is expected through Friday with an increase in night through morning low clouds. A frontal system may bring rain to the entire area by Thursday night and Friday. Dry and warmer weather is expected for the weekend but a cold upper low will bring cooler temperatures and windy conditions early next week.
Daytime temperatures continue to cool as onshore flow increases and a trough approaches from the northwest. A deep marine layer exists and is expected to be slightly deeper Thursday morning with additional cooling aloft. Can't rule out some drizzle Thursday morning, mainly near the south facing foothills. Probably not a lot of clearing for coast/valleys Thursday but regardless temperatures will be 5-15 degrees below normal, with the bigger anomalies inland and/or at higher elevations. Expect lows in the 50s and highs in the 60s to low 70s.
The trough from the north will arrive Thursday night then moving inland onshore Friday morning, bringing the area it's best chance for precipitation. Still looking like a light rain event with amounts mostly under a quarter inch, though upslope areas could see around a half inch.
Precipitation expected to taper off during the afternoon Friday with dry conditions Friday night through the weekend. Friday temperatures will mostly be in the 60s with lots of clouds and light showers but will rebound several degrees Saturday under mostly sunny skies and weakening onshore flow.
Marine inversion expected to be wiped out by Saturday morning following the trough passage and increasing northwest flow the so marine layer stratus will be highly disrupted. A second trough passage Saturday afternoon should have minimal impact except to provide additional support for increasing northwest flow Saturday afternoon for potentially advisory level winds in southern Santa Barbara County Saturday evening.
Sunday should be the warmest in this 7 day stretch with light offshore flow to start and mostly sunny skies. Valley expected to jump into the 80s while most coastal areas away from the immediate coast should be in the mid 70s.
Big changes on tap for Monday/Tuesday as a cold upper low drops into the state from the north. The trajectory with this one continues to be more inside which is not favorable for precipitation but doesn't make it impossible. Given the amount of cold air aloft it wouldn't take much to squeeze a shower out late Monday into Tuesday, especially in the mountains.
