Severe storms caused damage across Northern California on Saturday, and for the first time in history, the National Weather Service (NWS) issued a tornado warning for the city of San Francisco.

The warning was issued shortly before 6 a.m. local time on Saturday and people were urged to seek shelter.

The warning ended at 6:15 a.m. as the storms moved north into San Francisco Bay and damage in the tornado-warned area in San Francisco was ultimately classified by the NWS as straight-line wind damage rather than a tornado.

The San Francisco Emergency Management Agency issued a statement about the tornado warning, noting that residents were “understandably anxious” to receive such an unusual warning for the region.

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They also advised residents that if San Francisco receives a tornado warning in the future, people should seek shelter on the lowest floor, away from windows, as few buildings in the city have basements.

There was already a confirmed tornado in San Francisco in 2005, but without a tornado warning. So the first confirmed tornado occurred without a tornado warning, while the city’s first tornado warning occurred without a confirmed tornado.

The storms caused flooding in some parts of the city and wider region, while gusts of wind toppled trees and knocked out power to homes and businesses in places like Seaside, Livermore and Monterey, California.

Confirmed tornado in Northern California

Preliminary damage assessments from the National Weather Service indicated the EF1 tornado had peak winds of 90 mph when it hit at 1:39 p.m. local time.

The tornado only stayed on the ground for five minutes, traveled a half mile and stretched 100 feet wide. During this short period of time, several vehicles overturned and power lines were destroyed.

Scotts Valley police told local media that at least five people were injured, most of them in overturned vehicles.

The heaviest damage occurred along Mount Hermon Road in the city’s shopping district. The road was closed Saturday as officials assessed the damage and crews worked to restore power.

About 3,600 customers in the area remained without power Sunday morning, according to PowerOutage.us.

California residents may have more experience with earthquakes than tornadoes, but the state experiences about 11 tornadoes per year on average.

What’s next for the region: Another storm system is expected to hit the West Coast early this week, and heavy rain is possible along the coasts of Washington, Oregon and Northern California.

The system will move inland by midweek and there is currently no risk of heavy rain or severe weather for the regions most affected by Saturday’s storms.

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