Snow dusts Bay Space peaks, flurry reported in San Francisco

A cold weather system from western Canada pushed across the San Francisco Bay Area on Monday night into Tuesday, delivering a dusting of snow to the region’s highest peaks.

Mount St. Helena in the North Bay, Mount Diablo in the East Bay, Mount Hamilton in the South Bay and the hills surrounding these peaks all saw accumulations of snow, the National Weather Service said.

Snow covers the Lick Observatory on Mount Hamilton in San Jose, Calif., on Dec. 14, 2021.

Lick Observatory webcam

A webcam shows snowfall covering the peak of Mount Diablo on Tuesday morning, Dec. 28, 2021.

CalFire

“As far as any measurable snow, it’s going to be above 2,000 feet to 2,500 feet, for this storm,” said Eleanor Dhuyvetter, a forecaster with the weather service. “Some people’s windshields in the North Bay had snow at 2,000 feet.”

Intermittent snowfall is expected on the highest peaks through Wednesday, and the weather service is projecting about a foot of snow accumulation on Mount Hamilton by tomorrow.

There have been some reports of a few flurries in the hills around the Bay Area this morning!

Here is the 4am sounding! You can see a dry layer near the surface, this helps cool the air right above the surface as the precip is falling. pic.twitter.com/51w9WZOpE0

— NWS Bay Area (@NWSBayArea) December 28, 2021

Dhuyvetter said snow flurries, light snow with no accumulation, were reported at elevations as low as 500 to 1,000 feet early Tuesday before sunrise.

A weather service spotter in San Francisco just north of Twin Peaks reported a flurry.

“He said he was at around 200 feet, but he also was in a favorable position on the southeast side of a hill. … We had storms coming from the northwest and there would have been some uplift setting up a more favorable situation where he was on the southeast side to see snow,” Dhuyvetter said.

So even though our snow level was at 2500ft this morning, the dry air allows that to lower to around 1500ft as precipitation is falling (due to evaporative cooling). So hilly areas will get closer to that 1500ft level. pic.twitter.com/p3wa0UbL5j

— NWS Bay Area (@NWSBayArea) December 28, 2021

Snow levels are expected to rise to about 3,000 feet late Tuesday morning and through the afternoon, as another wave of precipitation moves across the region. Dhuyvetter said they may drop back down as low as 2,500 feet overnight.

The Bay Area’s peaks have seen intermittent snowfall since Sunday, but late Monday into early Tuesday morning, temperatures dropped as a blast of cold air moved into the region, bringing the highest chances for snow the region has seen this season.

A spell of dry weather is forecast to begin Thursday and continue through the weekend.