4.7 quake near Truckee triggers earthquake early warning alert

A magnitude 4.7 earthquake was reported Thursday night 11 miles northwest of Truckee, according to the U.S. Geological Survey.

The earthquake early warning app MyShake sent out an earthquake early warning as far away as the San Francisco Bay Area, suggesting a magnitude 6 quake had occurred in Placer County, between the north shore of Lake Tahoe and the town of Truckee.

The quake’s magnitude was quickly revised downward to 4.7 on the U.S. Geological Survey’s website for the quake, which struck at 9:35 p.m.

The strongest shaking — moderate as defined by the Modified Mercalli Intensity Scale — was calculated by the USGS as only occurring in a remote, mountainous area of the Sierra Nevada northwest of Truckee, along the border of Sierra and Nevada counties.

Light or weak shaking was felt in Truckee, according to people who filled out the USGS’ Did You Feel It? form on its website.

“Pretty good jolt here in Truckee,” tweeted Neil Lareau, professor of atmospheric science at the University of Nevada, Reno.

Seismologist Lucy Jones on Twitter said the epicenter of the quake is near the location of a magnitude 6 quake in 1966.

The earthquake occurred 13 miles from Carson City, Nev., 16 miles from Reno and 25 miles from South Lake Tahoe, Calif.

In the last 10 days, there has been one earthquake of magnitude 3.0 or greater centered nearby.

An average of 25 earthquakes with magnitudes between 4.0 and 5.0 occur per year in California and Nevada, according to a recent three-year data sample.

The earthquake occurred at a depth of 5.0 miles. Did you feel this earthquake? Consider reporting what you felt to the USGS.

Find out what to do before, and during, an earthquake near you by reading our five-step earthquake preparedness guide.