Roger Gass, a meteorologist with the weather service’s Bay Area office, said he doesn’t expect the atmospheric river to stall, which typically would mean higher rainfall totals.
He said the heaviest rainfall could happen around commute time on Thursday morning.
Forecasters expect the system moving toward the region from the Pacific Ocean to “pack a punch” when it comes to winds along the coast. A high wind warning is in effect from 10 p.m. Wednesday through 10 a.m. Thursday morning for the coastal North Bay, the Marin hills and down the San Francisco Peninsula, with gusts potentially exceeding 60 mph.
People hold umbrellas as they cross 24th and Mission streets in San Francisco on Dec. 13, 2021. (Beth LaBerge/KQED)
As for the rest of the region, the service issued a wind advisory for the same time period, with winds up to 25 mph and gusts up to 50 mph.
“Just be ready for isolated to widespread power outages as weaker trees and limbs fall in these wind speeds,” Gass said. “I would encourage folks to delay travel in the morning, if they don’t have to be anywhere, as it’ll be during the brunt of the rush hour traffic.”
An atmospheric river is a massive corridor or “river” of concentrated water vapor in the atmosphere that can behave erratically, soaking a region when it stalls. Weather experts measure the intensity of atmospheric rivers on a scale from 0 to 5.
