Hurricane Erin, which briefly intensified into a Category 5 storm Saturday morning, weakened to a Category 3 by the evening as it underwent an eyewall replacement cycle in the Atlantic, forecasters said.

U.S. shores are unlikely to see a direct hit, but a strong offshore hurricane can produce massive and dangerous waves well away from its center.

The storm will remain a major hurricane through the middle of the week, according to the National Hurricane Center.

Erin, the first hurricane of the season, is now a powerful Category 5 hurricane. Here's where it could head in the week ahead.