Tropical Storm Bertha formed near the South Carolina coast on Wednesday, shortly before making landfall near Charleston. A Tropical Storm Warning is in effect from Edisto Beach to the South Santee River, and heavy rainfall is expected, the National Hurricane Center said.
The center said tropical storm conditions are forecast to continue near the coast over the next few hours.
"Bertha is expected to produce total rain accumulation of 2 to 4 inches with isolated totals of 8 inches across eastern and central South Carolina into west central to far southeastern North Carolina and southwest Virginia," it said.
The rain could lead to life-threatening flash flooding and aggravate ongoing river flooding.
Bertha is the second tropical storm to form this year before the Atlantic hurricane season's official start on June 1.dumped heavy rain on the East Coast earlier this month after forming near Florida.
The Associated Press reports this is the sixth year in a row that a named storm has formed before June.
After it heads inland, Bertha is expected to weaken to a tropical depression later on Wednesday, according to the hurricane center.