A magnitude 3.3 earthquake rattled the Riverside County mountains and Coachella Valley in the predawn hours today, USGS seismologists said.
The 1:59 a.m. shaker had an epicenter 10 miles south-southeast of Idyllwild, or 18 miles south-southwest of Palm Springs.
It was also plotted at 4 miles north of Anza, in northeast San Diego County. The epicenter was 64 miles north-northeast of San Diego.
Its center of movement was an estimated 2.4 miles beneath the earth's surface, according to scientists who reviewed the automated detection data.