Hurricane Erin has been downgraded to a Category 3 hurricane but is gaining in size and raising the risk of life-threatening surf later this week along the U.S.

After forming Monday morning in the eastern Atlantic Ocean, Tropical Storm Erin has officially strengthened into the first hurricane of the 2025 Atlantic season. The storm spun to life just west of Africa’s Cabo Verde Islands.

Implications for the Leeward Islands: Residents and visitors in St. Thomas, St. John, St. Croix, Puerto Rico and the northern Leeward Islands should monitor this system throughout the week. Even if the wave remains weak, increased moisture could bring showers, gusty winds and higher seas toward the end of the week.

Storms that ramp up so quickly complicate forecasting and make it harder for government agencies to plan for emergencies. Hurricane Erick, a Pacific storm that made landfall June 19 in Oaxaca, Mexico, also strengthened rapidly, doubling in intensity in less than a day.

Much of North Carolina’s Outer Banks region is under a tropical storm watch with Hurricane Erin expected to skirt the area Wednesday through Thursday, according to the National Hurricane Center.

A disturbance in the Atlantic following Hurricane Erin is now expected to track northward, according to NHC data.