Hurricane Helene caused a severe landfall on Thursday night in northwestern Florida as a Category 4 storm. Forecasters warned that the enormous system could create a “nightmare” storm surge and bring dangerous winds and rain across much of the southeastern U.S.

The National Hurricane Center in Miami said Helene roared ashore around 11:10 p.m. EDT near the mouth of the Aucilla River in the Big Bend area of Florida’s Gulf Coast. It had maximum sustained winds estimated at 140 mph (225 kph). This location was only about 20 miles northwest of where Hurricane Idalia came ashore last year at nearly the same ferocity and caused widespread damage.

Helene prompted hurricane and flash flood warnings that extended far beyond the coast, reaching into northern Georgia and western North Carolina. According to the tracking site poweroutage.us, more than a million homes and businesses were without power in Florida, and over 50,000 in Georgia. The governors of Florida, Georgia, Alabama, the Carolinas, and Virginia all declared emergencies in their states. In Florida, one person was killed when a sign fell on their car, and two people were reported killed in a possible tornado in south Georgia as the storm approached.

“When Floridians wake up tomorrow morning, we’re going to be waking up to a state where very likely there’s been additional loss of life and certainly there’s going to be loss of property,” Florida Gov. Ron DeSantis said at a news conference Thursday night.The National Weather Service in Tallahassee issued an “extreme wind warning” for the Big Bend as the eyewall approached: “Treat this warning like a tornado warning. Take shelter in the most interior room and hunker down!”