Strong Storm in San Francisco Brings a Tornado Warning

Powerful storms swept through parts of Northern California on Saturday, knocking down trees, causing widespread power outages and prompting weather officials to issue what they said was the first-ever tornado warning for San Francisco.

The warning blared from cellphones around 5:45 a.m., jolting residents across the city from their sleep and into the sudden realization that many had long prepared themselves for what to do in the case of a sudden earthquake, but not a tornado.

And it came less than two weeks after a similar alert echoed across the Bay Area warning of a different kind of disaster scenario: an impending tsunami that forecasters worried could strike along a vast stretch of the Northern California coast.

That warning had been spurred by an earthquake in the Pacific Ocean and briefly caused a panic as people sought to get to higher ground. The warning was canceled a little more than an hour after it was issued.

The tornado warning on Saturday, which was in effect for about 30 minutes, was urgent: “Take shelter now in a basement or an interior room,” it read in part.

“That is the first time that we’ve issued a tornado warning for San Francisco,” said Crystal Oudit, a meteorologist with the National Weather Service in the Bay Area. She said the service had done so after seeing conditions that tend to favor tornadoes as the storm approached the city.