September 23, 2016 – Dry through the middle of next week. Breezy north winds through the weekend. Slightly below normal temperatures today then well above normal over the weekend and into next week. Cooling to near normal by the end of the week.
Discussion
Flat high pressure over the region will bring dry conditions and warmer temperatures today. The upper low which brought isolated thunderstorms to the Sierra on Thursday has shifted eastward and northerly flow has developed behind.
A weak frontal system moving into the Pacific Northwest will bring some clouds across the northern CWA today but warmer airmass will still bring daytime highs up to just a bit below normal.
Upper ridge amplifies over the west coast on Saturday bringing a warm up to several degrees above normal. A moderate northerly surface gradient with some upper support will bring breezy north winds through the weekend but nothing too significant. Building ridge brings even more warming on Sunday with daytime highs forecast to come in around 10 degrees above normal. Upper ridge axis shifts inland on Monday. This will bring a more onshore flow to the area along with a leveling off of daytime highs.
Extended discussion (Tuesday through Friday)
Strong high pressure forecast to weaken and shift east as deeper troughing pushes into the West Coast towards the end of the week. Dry weather expected with main impact for Interior NorCal being a cooling trend with increasing onshore flow. High temperatures expected to return around average.