Tropical Storm Elsa carved a destructive and soaking path up the East Coast after killing at least one person in Florida and spinning up a tornado at a Georgia Navy base that flipped recreational vehicles upside-down and blew one of them into a lake.

Elsa’s winds strengthened Thursday to 50 mph (85 kph), as the storm dropped heavy rains on parts of North Carolina and Virginia, the U.S. National Hurricane Center said in an update. Elsa was passing over the eastern mid-Atlantic states on Thursday night and was expected to move near or over the northeastern United States on Friday.

No significant change in strength is expected through Friday, and Elsa is forecast to become a post-topical cyclone by Friday night, the center said.

Read:Tropical storm kills 1 in Florida, hurts 10 at Georgia base

Tropical storm warnings were in effect along the coast from North Carolina to Massachusetts. There was a chance Long Island in New York would see sustained tropical storm-force winds late Thursday night and into Friday morning, the National Weather Service in New York warned.

The National Weather Service in Morehead City, North Carolina, tweeted that a tornado was spotted near Fairfield on Thursday afternoon. A tornado warning had been issued for Hyde County and surrounding counties.

Elsa seemed to spare Florida from significant damage, though it still threatened flooding downpours and caused several tornado warnings.

Authorities in Jacksonville, Florida, said one person was killed Wednesday when a tree fell and struck two cars. A spokesperson for the Naval Air Force Atlantic Office said Thursday that a sailor assigned to Patrol and Reconnaissance Squadron 16 in Jacksonville was killed.

Forecasters reported 50 mph (80 kph) wind gusts in the city. The tree fell during heavy rains, according to Capt. Eric Prosswimmer of the Jacksonville Fire Rescue Department.

Nine people were injured Wednesday evening in coastal Camden County, Georgia, when a tornado struck a campground for active-duty service members and military retirees at Kings Bay Naval Submarine Base. Eight of those hurt were taken to hospitals, base spokesperson Chris Tucker said. Some have since been released and others were kept for observation, he said.

Read:Elsa weakens to a tropical storm as it takes aim at Florida

The EF-2 tornado flipped over multiple RVs, throwing one of the overturned vehicles about 200 feet (61 meters) into a lake, the National Weather Service said in a preliminary report early Thursday after its employees surveyed the damage.

Tucker said about a dozen recreational vehicles at the campground were damaged. Some buildings were also damaged on the base, which is the East Coast hub for the Navy’s fleet of submarines armed with nuclear missiles. Tucker said there was no damage to submarines or any other “military assets.”

Sergio Rodriguez, who lives near the RV park, said he raced to the scene fearing friends staying at the park might be hurt.

“There were just RVs flipped over on their sides, pickup trucks flipped over, a couple of trailers had been shifted and a couple of trailers were in the water” of a pond on the site, Rodriguez said in a phone interview.

In South Carolina, a Coast Guard Air Station Savannah crew rescued a family that became stranded on Otter Island on Wednesday after their boat drifted off the beach due to Elsa. A man, his wife and daughter, and three cousins were hoisted into a helicopter and taken to Charleston Executive Airport in good health Wednesday night, the Coast Guard said in a news release.

The hurricane center said rainfall totals between 2 to 4 inches (5 to 10 centimeters) were expected through Friday for eastern Mid-Atlantic states and into New England. Isolated totals up to 6 inches (15 centimeters) were possible. There was a risk of “considerable” flash and urban flooding.

Read:Officials: Storm lashing Florida strengthens into hurricane

More than 7 inches (18 centimeters) of rain was recorded at a weather station near Gainesville, Florida, the weather service reported.

Scattered power outages were being reported along Elsa’s path Thursday night, with about 45,000 homes and businesses without electricity from Virginia to Massachusetts, according to the website poweroutages.us.

Elsa is the earliest fifth-named storm on record, said Brian McNoldy, a hurricane researcher at the University of Miami.