Forecasters say the same weather system responsible for dozens of tornadoes and flash flooding in the Midwest and Deep South could bring three rounds of severe weather to the Charlotte region over the next 48 hours.
The first threat is expected in the Carolinas late Monday night and early Tuesday, as storms that battered Georgia and Tennessee during the day Monday moved into a rapidly destabilizing atmosphere, especially over the southern half of North Carolina and Upstate South Carolina.
Additional rounds are expected Tuesday afternoon and evening, then again Wednesday morning and afternoon. Wind and hail damage is possible in any of the three periods of stormy weather, forecasters said, but the flooding threat is expected to grow later Tuesday and Wednesday.
A flash flood watch has been posted for the entire Charlotte region until midnight Thursday. Severe thunderstorm and tornado watches also are likely at times over the next two days.
North Carolina Gov. Pat McCrory, who declared a state of emergency Monday in four northeastern counties hit by tornadoes late last week, warned residents of the entire state to use caution and be prepared for dangerous weather.
“This will be a very busy period over the next few days,” said Harry Gerapetritis, of the National Weather Service office in Greer, S.C.
Gerapetritis said meteorologists were especially concerned late Monday about the presence of a frontal system, stretching east to west and virtually bisecting the state. North of the front, temperatures Monday were in the low 60s in places like Raleigh and Greensboro. Charlotte, south of the front, experienced temperatures in the low 80s.
“That front is worrisome because it is often the trigger for severe thunderstorms and tornadoes,” Gerapetritis said. He said that threat would reach a peak early Tuesday morning, as thunderstorms from Alabama, Georgia and Tennessee move into the Carolinas. Typically, severe weather takes place along and just south of the front, in the warmer and more unstable air.
A relative lull is possible Tuesday morning as the first area of storms moves off to the east. But another strong round of showers and storms is expected to arrive in the afternoon and evening. Then a third and final round is forecast Wednesday as a cold front pushes across the Carolinas.
Computer models indicate 3 to 5 inches of rain will fall across the region, but some areas could receive much more if thunderstorms begin following the same path – a condition known as “training.”
North Carolina’s secretary of public safety, Frank Perry, urged residents to stay tuned to weather forecasts.
“We have all seen how quickly storms can strike, and it is extremely important for everyone to stay tuned to local weather reports,” Perry said. “Our goal is to stress the importance of being prepared.”
By Wednesday, forecasters say their biggest concern is that the relentless series of heavy showers and storms will cause flooding problems. They say urban flash flooding and stream flooding is most likely, but flooding on major rivers also is possible.