A slow-moving cold front combined with near record high moisture content in the atmosphere are leading to an increasing flash flood risk across South Carolina Thursday.
The National Weather Service had issued Flash Flood Watches for most of the state, where 2 to 6 inches of rain was expected Thursday. As of Thursday morning, a band of heavy rain and a few thunderstorms stretched from near Rock Hill to Newberry to Edgefield. Another batch of heavy rain was between Charleston and Hilton Head. The rain is expected to fill in as the day progresses.
Rises in streams and creeks, along with flooded roadways, are likely. As of Thursday morning's forecast, moderate flooding is forecast along the Congaree River at Carolina Eastman by the weekend from runoff. Additional rivers, including the lower Savannah and the Pee Dee, are expected to experience at least minor flooding from Friday into the upcoming weekend.
Tropical Storm Eta over northern Florida was also aiding in the transport of moisture northward into the state. It is forecast to move into the Atlantic near Jacksonville Thursday afternoon. The cold front primarily responsible for the heavy rain across the Palmetto State is expected to follow behind and move offshore early Friday. Drier weather is forecast statewide to start the weekend, except for a few leftover showers in the Pee Dee and Grand Strand regions of the state.