SAN FRANCISCO (KGO) -- The Ferndale earthquake was a big "success" for California's earthquake early warning system. Three million Californians got an alert. At 2:34 a.m., hundreds of thousands of Bay area residents were jolted out of bed by an earthquake alert on their cell phone.
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Some woke up and saw the "drop, cover and hold on" message and jumped out of bed and got into a doorway. Some felt shaking. Many did not.
California's shake alert system started delivering alerts to the MyShake app in 2019.
MORE: USGS explains what to do when you get a ShakeAlert earthquake warning notification
"We've sent over 65 or 70 alerts to various places in California, but this is the biggest alert we've sent out so far," Richard Allen, the director of the UC Berkeley seismology lab said. "This alert went out to 270,000 users of the the MyShake app last night. The alerts are only sent to people we expect to feel shaking intensity three or greater level shaking in an earthquake where we expect the magnitude to be greater than 4.5. So if you get the alert you should drop, cover and hold on."
The amount of warning depends on how far away you are from the epicenter. If you're close, maybe you get only one second of warning. If you are further away like Monday night in the Bay Area, you could have a full minute before you feel the shaking. Plenty of people felt it according to USGS, from San Jose to Medford, Oregon.
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"That's the value of early warning - so people protect themselves, they don't fall over or have things fall on them and we can significantly reduce the number of injuries," Allen said.
At a press conference after the quake, California OES urged more residents to download the MyShake app saying we live in earthquake country.
"A 6.4 in Ferndale is very different than a 6.4 in downtown San Francisco, so having had this experience, people in the Bay Area being made aware of it to us - this is all positive so they can be prepared for the next one," Brian Ferguson, OES deputy director of crisis communications said.
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