Georgia region hit with 'extreme' rainfall and flash flooding is under another flood watch

Areas in northwest Georgia that experienced “extreme rainfall” and flash flooding are again under a flood watch as storms move in Monday.

“Showers have begun to redevelop over north Georgia, and rain chances will continue to increase this afternoon and evening,” the National Weather Service office in Atlanta posted on Facebook. “Scattered thunderstorms will also be possible this afternoon, which could produce heavy rainfall and localized flooding concerns.”

Extreme rainfall led to downed trees in Chattooga County Sunday. - WSB

Rainfall in those parts of Georgia was so heavy Sunday, CNN Weather estimates it was a 1 in 1,000-year rainfall event, with parts of Chattooga and Floyd counties getting up to 13 inches.

That led to “catastrophic flash flooding,” the weather service said Sunday.

Georgia Gov. Brian Kemp issued a state of emergency order Sunday afternoon for severe flooding in Chattooga and Floyd counties, where an estimated foot of rain in some places was expected to cause rivers to rapidly rise, according to the order.

Businesses were under water in Summerville Sunday. - Courtesy Jennifer Hurley

“Preliminary assessments from county emergency management agencies and the Georgia Emergency Management and Homeland Security Agency indicate a need for assistance in the impacted counties,” the order read.

The city of Summerville in Chattooga County advised residents to boil all water to use for drinking, cooking or preparing baby food after flash flooding at a filter plant.

Schools in Chattooga County will be closed on Tuesday and Wednesday because the flash flooding left hundreds without drinking water.

“Without water, we are unable to flush toilets, wash hands, drink from the fountains or prepare lunches,” Chattooga Superintendent Jared Hosmer said in a message to the district on Monday.

North Georgia isn’t the only region under threat. Flash flood watches were also in effect Monday from Alabama to Maine, affecting more than 80 million people, including a long list of major cities: Birmingham, Atlanta, Nashville, Louisville, Cincinnati, Pittsburgh, Philadelphia, New York and Boston.

This year has already seen several notable 1 in 1,000-year rainfall events, including in St. Louis, eastern Kentucky and Death Valley.

CNN’s Chuck Johnston and Judson Jones contributed to this report.

For more CNN news and newsletters create an account at CNN.com