Not quite as warm today and Saturday. Cooler with a chance of showers later Sunday through Monday. Dry and gradually milder by the middle of next week.

Pattern change early next week


Occasional high clouds are moving across NorCal early this morning. Surface pressure gradients continue to trend toward onshore as the upper ridge slowly shifts east, and as a sign of the shifting seasons a moderate Delta Breeze persists at Travis AFB. Current temperatures are mostly running a bit cooler compared to 24 hours ago with the Central Valley currently seeing readings ranging from the upper 40s to lower 60s.

High temperatures today

Dry and mild weather will continue today and Saturday, though not quite as warm as the past several days where onshore flow has the greatest influence (Central Valley), as the upper ridge gradual shifts a little further to the east. A change toward cooler and more unsettled weather is expected to begin Sunday as the next upstream trough approaches.

Temperatures are forecast to lower about 10 degrees compared to Saturday, and a few showers will be possible along the western edge of the forecast area by late in the day.

Models continue to show the trough splitting early next week with a deep closed low moving slowly east-southeast along or off the California coast early next week. The latest deterministic models follow pretty closely with the 00Z Tuesday clusters lending confidence that most of the CWA will see some decent precipitation on Monday.

Precipitation forecast Sunday and Monday

However, as we’ve recently experienced, relatively minor changes in the track of these systems can have a dramatic impact on how far inland precipitation extends. Stay tuned.

Extended Discussion (Tuesday through Friday)

Ridge begins to build from the eastern Pacific Tuesday and flattens through the week, resulting in drier and warmer conditions through the extended period.

Daytime temperatures will be around 5-10 degrees above normal with Valley highs in the mid to upper 70s. Periods of breezy offshore winds may develop late in the forecast period.