South Carolina Flood Victims

Days of torrential rains kept much of South Carolina and its capital gripped by floodwaters early Monday as emergency responders promised renewed door-to-door searches for anyone still trapped after a weekend deluge and hundreds of rescues, The Associated Press reported.

At least seven weather-related deaths have been blamed on the vast rainstorm.

Heavy rain kept falling into the early hours Monday around the Carolinas from the storm that began swamping the Southeast late last week, part of an unprecedented low pressure system that dumped more than 20 inches on one spot alone in Columbia, the South Carolina capital, the AP said.

Sunday marked the wettest day in the history of Columbia, according to the National Weather Service. The rainfall total at the Columbia Metropolitan Airport was 6.87 inches, the most rain that's ever fallen there in one day.

"The flooding is unprecedented and historical," said Dr. Marshall Shepherd, a meteorologist and director of the atmospheric sciences program at the University of Georgia, in an email to the AP.

He said the unique double punch of the upper level low — aided by a "river" of tropical moisture in the atmosphere from Hurricane Joaquin spinning far out in the Atlantic — gave the monster rainstorm its punch.

The deluge made for otherworldly scenes in the state capital of Columbia as floodwaters nearly touched the stoplights Sunday at one downtown intersection. Rainwater cascaded like a waterfall over jagged asphalt where a road sheered apart and many cars were submerged under flooded streets.