Atmospheric River To Kick Off Series Of Storms In The Bay Area

SAN FRANCISCO — A series of wet weather systems promise to soak the Bay Area well into next week, and forecasters say Friday's first salvo has the makings of a classic atmospheric river.

In updates shared Thursday, the National Weather Service charted multiple rounds of moderate-to-heavy rainfall stretching as far as the forecast can see.

While the North Bay is likely to see the highest rain totals, new forecasts favor periods of heavy rain drifting considerably southward.

"The storm door opens on Friday, allowing for an atmospheric river to set up over the area," the weather service said. "[Model]-based precipitation totals have also increased, especially across the North Bay, San Franciso and East Bay areas."

Forecasters expect rain will begin to spread over the North Bay as early as Thursday night, and much of the Bay Area has an 80 - 100 percent chance of precipitation by noon Friday. More showers are on tap Saturday ahead of potentially more significant rainfall possible Sunday and lasting into next week.

The vast majority of the Bay Area is favored to record at least an inch of rain by early Monday.

Forecasters said the barrage of weather systems still carries a fair amount of uncertainty, but much of the Bay Area will see a slight risk of "excessive rain" on Saturday and Monday.

"This forecast will continue to be fine-tuned as we get into the hi-rez model guidance territory," the weather service said. "Be sure to keep up with the latest forecasts as rainfall totals and peaks will be fine-runed, which could result in changes in timing and areas of the excessive rainfall outlooks.