San Francisco receives first tornado warning

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

The warning went out just before 6 a.m. local time Saturday, and people were warned to take shelter.

The warning ended at 6:15 a.m. as the storms moved north into San Francisco Bay, and damage in the San Francisco tornado warning area was ultimately determined by the NWS to be straight-line wind damage, not a tornado.

San Francisco’s Department for Preparedness issued a statement about the tornado warning, noting that residents were “understandably anxious” to receive a warning so unusual for the region.

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They also advised residents that in the event San Francisco receives a future tornado warning, people should seek shelter in an interior space away from windows on the lowest possible floor, acknowledging that few buildings in the city have basements.

San Francisco has actually had a confirmed tornado before in 2005, but it came 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 in the wider region, gusts 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 said the EF1 tornado had top winds of 90 mph when it hit at 8 p.m. 13:39 local time.

The tornado was only on the ground for 5 minutes and it traveled a third of a mile and stretched 30 yards wide. In the short time it overturned several vehicles and tore down power lines.

The Scotts Valley Police Department told local media that at least five people were injured, most of them inside vehicles that overturned.

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

On Sunday morning, about 3,600 customers in the region remained without power, according to PowerOutage.us.

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

What’s next for the region: Another storm system is expected to affect the West Coast early this week, and heavy rain is possible for coastal Washington, Oregon and northern California.

The system will move inland by mid-week and there is currently no threat of heavy rain or severe weather in the regions most affected by Saturday’s severe weather.

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