Magnitude 6.4 earthquake strikes west of Nikolski, Alaska

A magnitude 6.3 to 6.4 earthquake hit west of Nikolski, Alaska on September 17, 2026, at 14:19:53 UTC, according to the U.S. Geological Survey.

USGS initially put the magnitude at 6.3, with the epicenter 167 km west of Nikolski at coordinates 52.810°N, 171.341°W and a depth of 83.00 km (51.57 miles). The agency later revised the magnitude to 6.4, shifting the epicenter to 163 km west-southwest of Nikolski at 52.544°N, 171.186°W and placing the depth at 114.80 km (71.33 miles).

The revised report's ShakeMap estimated a maximum intensity of V, up from IV in the initial report. Two public submissions to the USGS "Did You Feel It?" system recorded a maximum reported intensity of III for the 6.4 event. Both USGS reports included a link to the Tsunami Warning Center.