US: A magnitude-5.5 offshore earthquake occurs south of the Aleutian Islands, Alaska, Nov. 21

Event

A magnitude-5.5 earthquake occurred in the North Pacific Ocean south of the Aleutian Islands in Alaska at around 05:09 Nov. 21. The epicenter was about 75 km (47 miles) southeast of Nikolski. The tremor occurred at a depth of about 13 km (8 miles), and light shaking was probably felt throughout parts of the central Aleutian Islands. There have been no initial reports of damage or casualties as a result of the earthquake, and significant damage is unlikely. It could take several hours until authorities can conduct comprehensive damage assessments, especially in remote areas. Light aftershocks are likely over the coming days. The event has not prompted any tsunami advisories.

Officials may temporarily shut down transportation infrastructure in the tremor zone to check for damage. Minor disruptions could occur during shutdowns, but service will likely resume quickly if no damage is found. Utility outages are possible, particularly near the earthquake's epicenter.

Advice

Out of an abundance of caution, consider vacating multistory buildings where shaking occurred until authorities confirm their structural integrity. Monitor and plan for aftershocks.