Hurricane Erin, the first named storm of the 2025 Atlantic season, stunned forecasters by strengthening from a Category 1 to a Category 5 hurricane in roughly 24 hours on 15–16 August. Peak sustained winds reached about 160 mph, making Erin one of the fastest-intensifying Atlantic cyclones on record for so early in the season. NASA and International Space Station cameras captured the storm’s massive 3-D structure as hurricane-hunter aircraft reported a well-defined eye. Although the center remained well offshore, Erin’s outer bands caused flooding and power outages in Puerto Rico, forced swimming bans from Maryland to Delaware, and damaged infrastructure along parts of the U.S. East Coast. New Jersey declared a statewide emergency on 21 August ahead of the storm’s closest approach, while the National Weather Service warned of 45- to 50-mph gusts on Cape Cod and widespread minor to moderate coastal flooding. Rough surf shut down ferries, cancelled a music festival at Salisbury Beach, and left nearly 60 Massachusetts beaches closed. Powerful waves also destroyed eight of the ten remaining sea-turtle nests on Emerald Isle, North Carolina. By 23 August, the National Hurricane Center said Erin had weakened to a post-tropical cyclone about 425 miles south-southwest of Halifax, Nova Scotia, yet it still carried hurricane-force winds near 90 mph. Forecasters expect life-threatening rip currents and periodic coastal flooding to persist along the Mid-Atlantic and New England shores through the weekend even as some beaches in New York and North Carolina reopen. The agency is also monitoring two new Atlantic disturbances as the season enters its peak.