Just a day earlier, Ernesto had been downgraded to a tropical depression.
WILMINGTON, N.C. (AP) -- Tropical Storm Ernesto picked up steam with surprising speed in the warm waters of the Atlantic and built toward hurricane strength Thursday as it swirled toward the Carolinas, forcing the closing of ports and campgrounds.
Virginia's governor declared a state of emergency and hundreds of National Guardsmen were activated there and in the Carolinas. Forecasters issued a hurricane watch for the northern half of the South Carolina coast and the southern portion of the North Carolina shore.
Ernesto had been expected to come ashore Thursday night near the South Carolina-North Carolina line.
By midafternoon, its northern edge brought rain to the states' eastern counties, and its winds were 70 mph, just short of the 74 mph threshold for a hurricane. Its winds increased steadily through the day from around 40 mph overnight as the storm drew energy from the warm water.
Full of surprises
"In the world of meteorology, it's just one surprise after another," said Tom Matheson, a meteorologist with the National Weather Service in Wilmington.
Just a day earlier, Ernesto had been downgraded to a tropical depression, not even making the grade as a tropical storm.
Ernesto's wind was less a concern than the threat of flooding. Parts of North Carolina were already drenched by thunderstorms that began Wednesday. Ernesto was expected to bring half a foot of rain to some areas.
"We need some rain around here -- just not all at once," said Jean Evans, a convenience store worker on North Carolina's Holden Beach.
The National Hurricane Center also warned of a storm surge of 3 feet to 5 feet in the Carolinas.
The National Park Service closed some facilities on the Outer Banks, including two campgrounds near Cape Hatteras. The Coast Guard closed ports at Wilmington and Morehead City in anticipation of gale-force wind.
Ernesto briefly reached hurricane strength on Sunday, but lost much of its punch crossing mountainous eastern Cuba and was a tropical storm of about 45 mph by the time it blew ashore in Florida on Tuesday night. It weakened further as it moved over the state.
At 8 p.m., Ernesto was centered was about 75 miles south-southwest of Wilmington. It was moving north-northeast at about 18 mph, and its winds were not expected to grow much stronger before the storm reached shore.
No immediate evacuations were ordered in the Carolinas, though both states urged residents to keep abreast of forecasts and obey any instructions to get out of danger.
Virginia Gov. Timothy Kaine declared a state emergency, putting 200 National Guardsmen on duty and opening the state's Emergency Operations Center in suburban Richmond. North Carolina Gov. Mike Easley activated 200 National Guard troops and had other emergency teams on standby.
Flash floods were being reported in some coastal cities by midafternoon.
Sean Gainer was driving down a street in Wilmington when his car suddenly stalled in two feet of water. By the time he and others pushed it to safety, the water in the road had receded.
"I've driven in hurricanes and I've seen worse than this. That kind of luck just happens," he said.
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