Earthquake Swarm Update: USGS Downgrades Susanville Quake to 4.9 Magnitude
SUSANVILLE, Calif. — The U.S. Geological Survey (USGS) has revised the magnitude of the significant earthquake that struck near Susanville, California, on December 30, 2025, downgrading it from initial reports of 5.3 to 4.9. The event occurred at approximately 9:49 p.m. PST, with the epicenter 14 km NNW of Susanville at a depth of 5.3 km, contributing to ongoing shaking in Lassen County.
A persistent swarm of earthquakes has shaken the remote Northern California town of Susanville and surrounding Lassen County since late December, with the latest significant jolt registering a magnitude 4.9 on December 30, 2025, at approximately 9:49 p.m. PST. The U.S. Geological Survey (USGS) reported the epicenter about 8 miles north-northwest of Susanville at a shallow depth of 5.6 miles, amplifying the felt intensity and prompting reports of strong shaking from local residents.
