Rain, mountain snow, and breezy winds today. Isolated thunderstorms possible this afternoon. Brief period of dry weather returns Sunday into Monday morning before additional rain and snow are seen Monday into Tuesday. Unsettled weather continues mid to late week.
Discussion
A weather system is making its way onshore into Northern California early this morning with rain showers noted across the northern portion of the CWA around 1 AM. Precipitation is expected to increase in coverage across the Valley this morning with a band of heavier rain expected to traverse the Valley between 4-8 AM, before precipitation becomes more limited to the higher terrain in the mountains and foothills late this morning.
Snow levels have increased slightly for this event with the northern mountains and Coast Range generally from 4.5-5.5 kft this morning and the Sierra and southern Cascades generally staying at pass levels though the event.
Difficult and hazardous mountain travel is anticipated at times and the Winter Weather Advisory remains as is.
This afternoon, some isolated thunderstorms will be possible, mainly in the Valley and foothills east of I-5. HREF is signaling the best chances north of I-80 at this time, although some isolated storms cannot be ruled out in the Motherlode region as well. The main threats with any storms will be lightning, gusty wind, and small hail. This threat diminishes this evening.
Also, breezy south to west winds are anticipated this morning into the afternoon hours, with the highest gusts over mountain crests.
This quick moving system exits the area tonight with brief ridging returning over NorCal Sunday.
Near normal temperatures, lighter winds, and dry conditions are expected this day. The benign weather is short lived as another trough approaches the area on Monday.
The highest Valley QPF is expected in the northern Sacramento Valley, tapering off further south. Higher amounts are expected in the foothills and mountains, ranging from around 0.50-1.50″. Snow levels look to generally be at pass levels again, with several more inches of snow anticipated over the mountains. This system looks to be another quick hitter with dry weather expected for a period from late Tuesday into Wednesday morning.
Extended Discussion (Wednesday through Saturday)
Cool and unsettled pattern continues late next week. Ensembles generally in agreement that the mid-week ridge will shift east as another anomalously cold trough moves in on Thursday. Precipitation will likely begin spreading inland across NorCal later Wednesday with potentially another significant winter-like system for the mountains, but clusters indicate there could be some timing issues with the trough.
Ridging forecast for next weekend expected to bring a return of dry weather with temperatures close to average for late April.