San Francisco Bay Area Weather Forecast (Including Santa Cruz County) – (1 to 2 days) – Mostly cloudy nights and mornings near the coast, otherwise mostly clear inland today through Friday. Westerly winds 10 to 20 knots in the afternoons and evenings.  High temperatures in the high 50’s to low 60’s near the coast and into the upper 80’s in the far inland valleys. Low temperature mostly in the low 50’s to low 60’s but low 70’s for the far inland valleys.  

Extended Forecast for Central California (Including Napa County south to Monterey County and east into the Sierras –  (3 to 7 days – (08/19/17 -08/23/17) –  Mostly clear Friday night through Wednesday, but with night and morning low clouds near the coast spreading inland into coastal valleys at times, except staying near the coast Friday night through Saturday.  Partly cloudy over the mountains at times with a chance of showers and thundershowers Friday afternoon through Tuesday.  High temperatures mostly in the high 50’s to low 60’s to the high 70’s near the coast warming into mid 90’s for the far inland valleys.  A little warmer inland on Friday and Saturday then cooling again on Sunday. Low temperatures mostly in the 50’s to mid 60’s.

Extremely Long Range Weather Outlook Northern and Central California 8 to 15 days (08/24/17 – 08/31/17) – Mostly fair with late night and morning low clouds near the coast at times. Near normal temperatures

Extremely Long Range Weather Outlook Northern and Central California 16 to 20 days (09/01/07 – 09/05/17) – Mostly fair during the period except for late night and morning low clouds and patchy fog near the coast at times. Near normal temperatures

Short Term Weather 1 to 7 day Forecast Discussion – A weak upper level trough continues over Northern California today that is bringing onshore flow.   Low clouds will continue nights and mornings near the coast moving inland late night and morning hours through Thursday and again Sunday into next week.  Higher pressure will continue across the Western United States over the next few days bringing hot temperatures to the far inland valleys through the remainder of the week into next week, but temperatures will continue cooler near the coast through the extended period.  The high will expand into California on Friday bringing a little warming to inland temperatures. Showers or thundershowers will be possible over the Sierras on Friday into early next week from an upper level system that develops near the coast over the weekend.

Northern and Central California 8 to 15 day extended forecast–  Little change in the weather pattern is expected with continued high pressure over the western United States and west to southwest winds aloft keeping onshore flow and near normal temperatures closer to the coast. 

Northern and Central California 16 to 20 day extended forecast–  A weak trough near the west coast and high pressure inland should continue to bring onshore winds and the marine layer near the coast. Temperatures average near normal through the period.