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False Earthquake Alert Shocks California; USGS Investigates

12/6/2025

46 7 Full Breakdown

Summary

Story summary

On December 4, 2025, the U.S. Geological Survey (USGS) ShakeAlert system issued a false alert for a magnitude 5.9 near Carson City, Nevada.
The alert, sent at 8:06 a.m., buzzed phones across California, including the San Francisco Bay Area.
USGS retracted the alert, stating no earthquake occurred.
Investigations are underway to determine the cause, as this was the first erroneous ShakeAlert alert since its 2019 launch.

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Story summary

On December 4, 2025, the U.S. Geological Survey (USGS) ShakeAlert system issued a false alert for a magnitude 5.9 near Carson City, Nevada.
The alert, sent at 8:06 a.m., buzzed phones across California, including the San Francisco Bay Area.
USGS retracted the alert, stating no earthquake occurred.
Investigations are underway to determine the cause, as this was the first erroneous ShakeAlert alert since its 2019 launch.