February 20, 2024 – Scattered showers and thunderstorms will continue today with periods of heavy snow over the mountains resulting in travel impacts. Decreasing showers are forecast Wednesday with mainly dry weather expected heading into the weekend.
Discussion
Radar shows scattered to numerous showers continuing across the region early this morning, mainly to the north of I-80. A few of these shower bands are accompanied by brief heavy rain and may may impact travel at times.
Intermittent bands of heavy snow persist over the Sierra with the snow level remaining around 5-6k ft.
The surface pressure gradient has relaxed since Monday evening and wind gusts have decreased, however local gusts up around 30 mph will persist across the northern Sacramento Valley through the remainder of the night.
The upper trough off the coast is forecast to split today with a strong short-wave trough headed toward SoCal while weaker flow moves over NorCal.
It is expected to be another active weather day with showers and thunderstorms, but weaker shear will limit the overall severe threat. However, stronger persistent storms that develop will still pose a risk for heavy rain and localized flooding along with large amounts of small hail.
In the Sierra, intermittent snow showers are expected with lighter overall snow accumulations forecast across the higher elevations compared to the past few days.
The trough is forecast to continue weakening on Wednesday with a few lingering showers possible, mainly over the mountains.
By Thursday, short-wave ridging will likely result in dry and milder weather for the region, but the next upstream trough will be closing off offshore to our west and may lead to a low chance for showers along the western edge of the valley and over the Coast Range.
Extended Discussion (Saturday through Tuesday)
Models are slowing progression of the closed upper low off the SoCal this weekend. Forecast now looks dry Saturday, and it’s not until Sunday afternoon that NBM/GFS introduce some POPs, mainly over the eastern mountains/Sierra Nevada.
Colder short wave troughprogged to drop into the CWA from the NW on Monday bringing some showers to the area, best chances over the mountains. Snow levels expected around 3500 to 5000 feet.
Drier weather likely Tuesday as EPAC upper level ridging builds inland.