Tropical Storm Ernesto has made landfall on the North Carolina coast, bringing heavy rains and winds just below hurricane strength.
Some residents are more worried about the rain than the wind
More than eight inches (20cm) of rain fell around the Wilmington area, and forecasters warned of more to come.
The governors of both North and South Carolina have activated National Guard troops, while the Virginia governor has declared a state of emergency.
Forecasters issued warnings of tornadoes and storm surges.
Ernesto made landfall near Cape Fear in North Carolina at 2330 (0330 GMT).
It is packing maximum sustained wind speeds of 70mph (113 km/h) - just below the 74mph threshold for it to be declared a hurricane. It is moving north-northwest at 18mph, said the National Hurricane Center.
It brought heavy rain to both North and South Carolina from mid-afternoon on Thursday.
Power companies reported some outages and some roads were flooded.
Some ferry services, ports and campsites were closed, though no evacuations have been ordered in either state.
A tropical storm warning remains in effect from north of the South Santee river to Currituck Beach Light, forecasters said. A hurricane watch is in effect from South Santee river to Cape Lookout in North Carolina.
Forecasters also warned that storm surges of up to five feet above normal tide levels were possible along the North Carolina coast, and that heavy rain of up to 10 inches could fall in north-eastern South Carolina into the mid-Atlantic states.
They say Ernesto could spawn isolated tornadoes in parts of North Caroline and Virginia.
For North Carolinians, some rain is welcome after a widespread summer drought, but residents fear a repeat of catastrophic flooding caused by Hurricane Floyd in 1999.
"We need some rain around here - just not all at once," convenience store worker Jean Evans told Associated Press from North Caroline's Holden Beach.
Ernesto is threatening the US for the second time
Ernesto was briefly the year's first hurricane on Sunday when its winds reached 75mph before it weakened over the mountains of Haiti.
The storm killed at least two people in Haiti before striking Cuba, where it dropped up to seven inches of rain before fading into showers and thunderstorms.
It began intensifying after passing over Cuba and forecasters had feared it could come ashore at hurricane strength. But in the end Ernesto passed through Florida as a weak tropical storm.
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