A magnitude 5.1 earthquake shook Southern California on Sunday afternoon, as much of the region began to feel the effects of Tropical Storm Hilary.

The U.S. Geological Survey (USGS) said the earthquake’s epicenter was about 4 miles southeast of Ojai, California, about 80 miles northwest of Los Angeles.

According to the USGS, the magnitude 5.1 earthquake happened at 2:41 p.m. PT.

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Several smaller aftershocks occurred after the earthquake, ranging from magnitude 2.6 to 4.0.

The City of Calabasas posted to X that the earthquake was upgraded to a 5.1, though there were no reports of any damage.

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Just before the earthquake, residents reported getting an alert on their phone from the USGS Shake Alert system.

"Earthquake detected! Drop, cover, hold on. Protect yourself," the alert read.

The alert came as Tropical Storm Hilary was centered less than 100 miles from San Diego, California, Fox Weather reported.

Torrential rains are expected from the storm, which could trigger life-threatening flooding through Monday.