Rain and Some Snow in Bay Area Forecast (Plus, More Snow in the Sierra)

You want rain, Bay Area? It's coming, along with a possible dusting of snow.

A moderate winter storm is expected to drop 0.5 to 2 inches of rain on the Bay Area from Wednesday to Thursday, including snow in some of the region's highest elevations, meteorologists say.

The storm will move in Wednesday night, with most of the rainfall expected Thursday morning, said Spencer Tangen, a meteorologist in the National Weather Service's San Francisco Bay Area office.

"It definitely could impact the morning commute on Thursday as we get that band of moderate to heavy rain moving through," Tangen said.

Half an inch of rain is likely in urban areas, while coastal hills — like those in the North and South Bay — could get up to 2 inches. Meteorologists aren't expecting any major flooding, more likely nuisance ones, such as ponding of water on highways, Tangen said.

But a cold front accompanying the storm could move the snow level down to 3,000 feet on Thursday afternoon, Tangen said, meaning Bay Area peaks like Mount St. Helena, Mount Hamilton, Mount Diablo and Mount Umunhum could get 2-3 inches of snow. Higher regional elevations do get dustings of snow several times a year, he added.

"This kind of storm isn't too out of the ordinary with these snow levels," Tangen said. "But it's exciting when it happens because a lot of storms are too warm for snow."

The rain should taper off by Thursday evening, and Friday will be all clear just ahead of a weaker storm expected over the weekend, Tangen said. The Bay Area, which started off the rainy season fairly dry, has experienced some storms to help get the region back to normal — but is still lagging.

"These upcoming storms will help to make up some ground, but it would take quite a few decent storm systems to get to 100% again," Tangen said.

An area that has made up a lot of ground? The Sierra Nevada, where meteorologists are expecting 1-2 feet of snow ahead of the Martin Luther King Jr. Day holiday weekend and up to a foot more in higher elevations. In early January, researchers determined the snowpack near Lake Tahoe was at 97% of normal during the first manual survey of the season — "just just below where we need to be," said Emily Heller, a meteorologist in the NWS Sacramento office. "This will probably set us back to what we would historically see for mid-January."

Heller said the moderate winter storm — a cold system coming in from the northwest — was expected to move in Wednesday night and continue through Friday morning.

"It looks like there could be periods of heavy mountain snow, gusty winds, which could lead to maybe some whiteout conditions, and periods of dangerous travel over the Sierra during that time frame, especially Wednesday night through Thursday," added Heller, who cautioned holidaymakers against heading to the area on Thursday and instead wait until Friday.

The Sierra Nevada should experience the weaker storm on Saturday that's following the bigger mid-week one, she said. Those heading to the area for the weekend should be prepared for some snow on Saturday, making getting around in the mountains somewhat difficult.

"But overall ... Sunday looks like a great day to be skiing," Heller added.