Area Forecast Discussion
Issued by NWS Sacramento, CA
Issued by NWS Sacramento, CA
437 FXUS66 KSTO 052059 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1259 PM PST Mon Jan 5 2026 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Rain and snow ending tonight. - Next system Tuesday night and Wednesday brings light snow to Sierra above 5000 feet. - Dry weather with areas of morning fog and clouds starting again late week. && .DISCUSSION... ...Tonight and Tuesday... Upper trough remains offshore with diffluent area causing an area of light to moderate rain from west of Sacramento north to Shasta County. Snow has shifted out of the I-80/Highway 50 area so have cancelled the Winter Weather Advisory there but will keep the winter storm warning in effect further north but it should be able to be cancelled later this afternoon. Rain that is occurring will decrase this evening and overnight and really see no threat of impacts during this time so expect to be able to cancel the Flood Watch as well later this afternoon. Tuesday...the trough that brought us all the weather last several days closes off and slides to the south of us with a dry day. With all the rain lately expect morning fog to set up most areas. ...Tuesday Night through Thursday... Energy drops south from Gulf of Alaska and eventually digs out a fairly deep trough over the western U.S. This is much drier and cooler air then we have had for a while. As far as moisture should be limited to some lighter snow above 5000 feet in the Sierra with little to no precipiation in the valley. ...Friday and Beyond... Pattern is somewhat progressive and upper level ridge sets up over west coast for dry weather. This will likely also set up some Tule fog as well. Will fine tune this in the forecast as it gets closer. && .AVIATION... Rain showers continue in the Valley, mainly along and north of I-80, will keep central/northern Sac Valley TAF sites bouncing between MVFR/VFR status through next 24 hours. Surface wind gusts from the south up to 30 knots through around 02z Tuesday. Mountain snow continues, with snow levels around 4500-5500 feet. As rain clears out of southern Sacramento Valley TAF sites, shallow BR and FG may develop overnight from 13z Tuesday through at least 18z. && .STO WATCHES/WARNINGS/ADVISORIES... Flood Watch until 4 PM PST this afternoon for Central Sacramento Valley-Mountains Southwestern Shasta County to Western Colusa County-Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-Shasta Lake Area / Northern Shasta County. Winter Storm Warning until 4 PM PST this afternoon for Western Plumas County/Lassen Park. && $$