Local
Two Storms to Soak Bay Area This Week, With Thunder and 60 mph Gusts Possible
A wet weekend gives way to a stronger midweek system that could drop up to 5 inches of rain on the coast, trigger thunderstorms and bring high winds, forecasters say.
Two storm systems are lined up to drench the Bay Area this week, with the second packing the heavier rain, a chance of thunderstorms and wind gusts that could top 60 mph on the region's highest peaks, according to the National Weather Service.
The first storm arrived Sunday morning in the North Bay, pushed south by an area of low pressure off the coast of British Columbia, meteorologist Roger Gass said. It was expected to move slowly across the rest of the region and down to the Central Coast through the afternoon, bringing light to moderate rain.
Rainfall totals from that system were forecast to reach up to 1.25 inches in the coastal mountains of Sonoma and Marin counties, with about half an inch likely in interior parts of the East Bay and the southern Santa Clara Valley. Winds along the shoreline could gust to 30 mph.
Gass said flood advisories were not out of the question. "We're monitoring the CHP page and river gauges," he said.
He added that Sunday carried little risk of thunderstorms. "The greater threat would be the system Tuesday night into Wednesday, when we expect to see more widespread heavy rain," Gass said.
That second storm, driven by a separate low-pressure system from the Gulf of Alaska, could drop 2 to 3 inches across most of the Bay Area and 3 to 5 inches along the coast. "The bulk of the precipitation is forecast to move in on Wednesday morning and continue through Thursday afternoon," Gass said.
The midweek system also brings a higher chance of thunderstorms, estimated at 20% to 30% later in the week, along with stronger winds: gusts of 40 to 50 mph across the region and up to 60 mph at the highest elevations. Gass said the storm is drawing deeper moisture from the eastern Pacific, though meteorologists have not yet classified it as an atmospheric river.
The active pattern is expected to continue. In its area forecast discussion, the weather service said the pattern "remains active towards the end of, and beyond, the seven day outlook, with a lean towards precipitation totals above seasonal averages into the final week of November."
The weekend storms also delivered the season's first substantial Sierra snow, with up to 13 inches accumulating at Mammoth, Sugar Bowl and Homewood. The weather service's Reno office issued a winter weather advisory for elevations above 7,000 feet in the Tahoe Basin from 10 p.m. Sunday until 7 p.m. Monday, warning that 3 to 7 more inches of snow could cause travel delays during the Monday morning commute.
The back-to-back systems arrive as massive waves pound the Bay Area coastline, adding to the hazards for low-lying and coastal communities.