Tsunami warnings prompted gridlocked traffic as people tried to reach higher elevations in Hawaii, but the threat level was later downgraded.

Authorities issued tsunami alerts for Hawaii, Alaska and parts of the U.S. West Coast after a massive earthquake struck off a peninsula in Russia’s far east.

Tsunami threats in the Bay Area are over after waves from the massive 8.8 Russia earthquake reached the San Francisco coast early Wednesday morning, but California coastal communities continue to monitor rising wave activity.

The year’s strongest earthquake struck off Russia’s Kamchatka Peninsula, triggering tsunami warnings and advisories in Hawaii, California, Oregon and Washington.