A significant weather shift is on the horizon for Northern California, as National Weather Service Sacramento announces the start of active weather patterns expected to impact the region over the weekend and into the next week. Beginning today, residents can anticipate moderate rain, mountain snow, and the possibility of isolated thunderstorms as a series of weather systems move through, as per the National Weather Service.
Clear skies are expected this morning, but clouds will increase by late afternoon and evening. Temperatures will cool slightly from yesterday's high but will still be in the 70s at lower elevations and 60s at higher elevations. Winds will pick up with gusts between 15 to 25 mph through Sunday. There is some uncertainty about Sunday's weather, particularly the chance of thunderstorms, which are estimated at 10 to 20 percent south of the Interstate 80 corridor, as reported ny the National Weather Service.
As for precipitation, lower elevations might see about 0.25 to 0.5 inches of rain, while higher elevations could get 0.5 to 1.0 inches. Snow levels initially around 4000 to 5000 feet will drop to 3500-4500 feet later on Sunday. "th heaviest snowfall expected to occur Sunday afternoon and evening during this snow level transition, the majority of accumulating snowfall is still expected above 4500 feet," mentions the National Weather Service. They estimate 1 to 5 inches of snowfall between 4500 and 6000 feet, and 4 to 10 inches above 6000 feet - prompting a Winter Weather Advisory for certain areas.
The National Weather Service reports uncertainty beyond Sunday, with a chance of showers extending into Monday. There will be a brief break in precipitation on Tuesday before another system arrives that night. This system may bring higher rainfall in valley areas and snow accumulation of up to a foot in the mountains. There is a 40-70% chance of 6 inches of snow at elevations above 5000 feet. A cooling trend is expected for Wednesday and Thursday, followed by a slight warm-up by Friday. Active weather is expected for the second week of March, but details are still unclear.
In the realm of aviation, VFR conditions are expected to prevail across interior NorCal until around 05z Sunday. However, pilots should plan for possible southerly gusts up to 20 knots in the Valley and foothills, and up to 35 knots in the mountains. A Winter Weather Advisory is in effect from this evening to Monday afternoon for West Slope Northern Sierra Nevada and Western Plumas County/Lassen Park due to expected snowfall.
