June 21, 2019 – Breezy northerly winds and lowering humidity will bring elevated fire weather concerns today through Saturday. Warmer than normal over the weekend, followed by cooler temperatures next week.
Discussion
Temperatures across the region are generally running several degrees cooler than 24 hours ago as upper trough continues to dig into the Great Basin. Local gusts of 20-30 mph have been reported in the Central Valley early this morning, mainly north of the Sacramento area. High temperatures today expected to be near or slightly below normal, with mostly 80s in the Central Valley.
Main weather concern today is the increasing northerly winds, and the associated fire weather concerns. Peak wind gusts will be in the 30 to 40 mph range, mainly on the west side of the Sacramento Valley and adjacent foothills. The combination of gusty northerly winds and low humidity will result in critical fire weather conditions today into Saturday. Therefore, a Red Flag Warning remains in effect until 6 PM Saturday. Any activity that could spark a fire is strongly discouraged.
Daytime temperatures over the weekend are expected to trend 3 to 8 degrees above normal as the upper trough shifts eastward, and high pressure builds in. Look for Valley highs in the 90s, with 60s and low 80s over the mountains. Looking into early next week, ensembles support lowering heights across the region as an upper low moves out of the Gulf of Alaska. This will promote synoptic cooling across interior NorCal. Valley highs expected to be near or slightly below normal by Monday.
Extended Discussion (Tuesday through Friday)
Ensemble data continue to support a trough over the region during the middle of next week with temperatures below average. Weather is expected to remain dry with breezy to windy conditions at times under strong southwest flow aloft. Indications are that the trough will weaken by the end of the week resulting in warmer temperatures and less wind.