SAN FRANCISCO — A late-season atmospheric river over the Pacific is taking aim at northern and central California.
The National Weather Service says the “robust” plume of subtropical moisture is well offshore Wednesday but stretches all the way to Hawaii.
Forecasters say it’s not clear where it will make landfall, but will bring light rain to the Bay Area by Thursday and then widespread and potentially heavy rainfall Friday into Saturday.
The potential for flooding will be a concern in the Central Valley and in parts of the Sierra Nevada, where storm runoff could combine with melting snow at lower elevations. Snowfall will be limited to high elevations because of the storm’s warmth.
Southern California will be out of the picture, except for light rain over San Luis Obispo and Santa Barbara counties.
#AtmosphericRiver storm systems approaching the West Coast!
— NWS Sacramento (@NWSSacramento) April 4, 2018