What to Know About Tropical Storm Erin

The fifth named storm of the 2025 Atlantic hurricane season is expected to become the first to reach hurricane strength.

Tropical Storm Erin (R) builds in the Atlantic Ocean as it heads for the Caribbean Sea on Aug. 12, 2025. (NOAA/NESDIS/STAR - GOES - 19).

Tropical Storm Erin formed in the Atlantic Ocean on Aug. 11 and long-range forecast models predict it will become a major hurricane that could impact Puerto Rico and the Eastern Caribbean, as well as the U.S. East Coast and Bermuda.

As of the evening of Aug. 12, Erin was still more than 1,600 miles away from the Northern Leeward Islands and the edge of the Caribbean, but as eyes look eastward for what is expected to be the first hurricane of the 2025 season to form, here are some things to know about this storm.

Erin Expected to Become Major Hurricane

As of 5 p.m. on Aug. 12, the National Hurricane Center (NHC) reported that Tropical Storm Erin was moving fast across the Atlantic Ocean. The storm is expected to become a hurricane in the next couple of days, and to grow into a major hurricane by Sunday, Aug. 17. A major hurricane is one that is a Category 3 or higher with sustained wind speeds greater than 111 mph.