Potentially millions of people were startled awake Thursday morning by a premature test of the MyShake alert on their cellphones.
The alert sent at 3:19 a.m. Pacific time went off for many in the Bay Area 7 hours before it was scheduled for Thursday's Great ShakeOut earthquake drill in California.
The test alert came less than a day after a 4.2 magnitude earthquake centered in southern Sacramento County was felt across parts of the Bay Area. Many people reported receiving the MyShake alert when that quake struck around 9:25 a.m. PT Wednesday.
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Thursday's early morning, premature alert included a voice alert saying, "This is a test." The alert was scheduled for 10:19 a.m., and it seems time zones got mixed up.
An acknowledgement from MyShake on the social media platform X, formerly Twitter, reads "You might have gotten a test alert from the @MyShakeApp early today. We acknowledge that no one wants to get a test message this early and we are working with our #ShakeAlert technical partner to determine what happened."
