February 21, 2019 – A few showers linger into this evening, mainly across the northern Sierra, otherwise dry with breezy north winds today and Friday. Next chance of precipitation will be over the weekend.
Trough continues to carve slowly southward toward SoCal as main vort energy digs along the coast. Satellite/radar imagery shows much of the cloudiness and showers currently ongoing from about the Sacramento area southward with clearing skies over most of the Sacramento Valley. Current temperatures are cooler compared to 24 hours ago across much of the region and range from the teens and 20s in the mountains to the mid 30s to lower 40s across the Central Valley.
Snow showers will likely continue into this evening along the crest of the northern Sierra while precipitation chances will mostly end elsewhere by mid-morning. Additional snowfall accumulations of an inch or two will be possible across the higher mountain passes.
Increasing subsidence in the wake of the low along with tightening northerly surface pressure gradients will result in breezy north winds today across the Sacramento Valley. Gusts to around 40 mph will be possible this afternoon. Gradients gradually transition to more easterly later tonight allowing winds to slacken over the eastern half of the valley, but some breeziness will likely linger along the west side. A wind advisory has been issued.
Short-wave ridging expected to shift over NorCal on Friday continuing cool and dry weather with lighter north winds. Areas of frost will be possible in the morning for areas of the valley where the winds subside enough.
Precipitation chances return over the weekend, mainly for the northern half of the forecast area, as energy begins to undercut the blocking high over the Gulf of Alaska and make its way into NorCal.
Extended Discussion (Monday through Thursday)
Active weather pattern looks likely for the extended portion of the forecast with Monday and Tuesday looking to be the wettest days. Periods of moderate to heavy rain will be possible for the start of the work week, as a low pressure system will tap into tropical moisture. Snow levels are progged to rise to 4000-5000 feet for this AR event. Come Wednesday, the precip is forecast to move to the north; however, models deviate on how fast it will exit the region.