Additional strengthening is expected as the storm is forecast to “remain a large and dangerous major hurricane through the middle of this week,” the National Hurricane Center said.

Powerful Hurricane Erin has undergone a period of astonishingly rapid intensification — a phenomenon that has become far more common in recent years as the planet warms. It was a rare Category 5 for a time Saturday before becoming a Category 4, churning through the Atlantic Ocean north of the Caribbean.

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.

Hurricane Erin, the first major hurricane of the 2025 Atlantic hurricane season, rapidly intensified Friday night, with the storm now reaching Category 5 strength with sustained winds of 160 mph.