Showers will linger through the day with mountain snow causing travel impacts to the weekend travelers. Dry with breezy north wind early next week. Unseasonably warm weather by the middle of next week.
Discussion
Northern California radars are in precipitation mode this afternoon with Valley rain showers and mountain snow showers. Rain amounts have been rather meager in the Valley with the initial wave of precipitation that pushed through during the morning hours. Some Valley airports that that have reported measurable rainfall through 1 PM PDT include Redding, Red Bluff, and Stockton. Sacramento-area stations have either traced or reported nothing.
The higher stratiform cloud bases combined with the drier layer between the surface and cloud bases resulted in the virga for much of the morning hours. For the rest of the day, high-resolution models have indicated the potential for some afternoon convection in the Valley and foothills, with the possibility of an isolated thunderstorm or two.
Latest HRRR guidance depicts upward of 100-300 J/kg most unstable CAPE throughout much of the Sacramento Valley. SPC Day 1 guidance was updated earlier today to include the general thunder risk for most of the Central Valley. Any strong showers or isolated thunderstorms that do develop have the potential to produce brief heavy downpours, lightning, small hail, and gusty/erratic winds.
Snow showers in the mountains will continue to bring travel- related impacts to motorists in the form of chain controls and travel delays. Motorists are always advised to check with Caltrans for the latest road conditions. Snowfall in the northern Sierra will generally remain on the light side with storm total of 2 to 6 inches above about 5500 ft, with locally higher amounts going up in elevation.
Precipitation will diminish overnight with dry and breezy north/east winds expected for Sunday. Wind-related impacts will be limited as the gusts are expected to remain between 20-30 mph in the Valley, and locally stronger gusts for the wind-prone mountain gaps, peaks, canyons, and ridgetops. Heading into the next workweek, ensembles and cluster analysis continue to indicate a rapid day-to-day warming trend region-wide by Tuesday.
Expect widespread 80s to be realized with additional warming by Wednesday (see extended for more details).
Extended Discussion (Wednesday through Saturday)
Widespread 80s will continue on Wednesday as an anomalously strong upper-level ridge axis centers over the West Coast. This will boost temperatures to around 15-25 deg F above normal.
Some locations in the central/northern Sacramento Valley may flirt with the 90 deg F mark, including Redding, Red Bluff, and Chico.
Latest National Blend of Models gives roughly a 20-30% chance of exceeding 90 deg F in the northern Sacramento Valley for Wednesday, March 23.
Compared to 1991-2020 climatology, the average first 90 deg F day for these locations is early May.
Ridge axis starts to pivot inland on Thursday, resulting in a degree or two of cooling for most locations. Dry conditions are forecast to prevail in the extended through at least next week Saturday.