After a freezing winter storm shut schools, cut power and canceled or delayed flights, the South was slowly thawing Sunday as weather warmed.

Crews worked furiously and by Sunday morning power had been restored to parts of North Carolina and South Carolina where tens of thousands of customers lost electricity over the last few days, according to Duke Energy.

Power was back for 97% of the retail customers served by Georgia Power — the state largest utility — which serves all but four of the state’s 159 counties, it said.

“Crews have not slowed down, in fact, we have brought in additional resources to help us get across the finish line,” read a press release on The City of Atlanta Government’s Facebook page.

Much of the winter weather has moved out of the area, said Dylan Lusk, a National Weather Service meteorologist in Peachtree, Ga.

“For the most part, we are slowly warming up and finally thawing a little bit after snow fall and a coating of freezing rain,” Lusk said.

Warmer weather was expected but some areas were still dealing with ice and authorities warned people to drive slowly and be careful with slick spots on roads — especially when temperatures drop again at night and melted snow and ice refreezes.

“Black ice will return as temperatures drop below freezing this evening through Monday morning,” the National Weather Service said.

Planes needed deicing and more than 100 flights to and from Hartsfield-Jackson Atlanta International Airport were delayed on Sunday — an improvement from Saturday, when 1,000 flights were canceled or delayed, according to FlightAware.com. By midafternoon Sunday operations had returned to normal, airport officials said.

Earlier this week the storm brought heavy snow — as much as 7 inches in some spots — and made roads slick across much of Texas and Oklahoma before moving east.

In some cities, the storm piled up more than a year’s worth of snowfall. As much as a foot fell in parts of Arkansas. In Memphis, a city that usually sees 2.7 inches a year, the Memphis International Airport recording more than 7 inches.

Atlanta was hit with more than 2 inches of snow on Friday, according to the National Weather Service. The agency said it was the first time the city had over an inch of snowfall since 2018.

While the National Weather Service says that Gulf Coast residents can expect showers Sunday and Monday, other parts of the country may see snow and brace for a mass of cold, dry air from the Arctic region — including in the Great Lakes region.

Although conditions are expected to improve, some places — including churches — announced closures for Sunday.

School was canceled on Friday for millions of children from Texas to Georgia and as far east as South Carolina, giving them a rare snow day. On Saturday, officials in northern Alabama said schools could remain closed Monday if ice doesn’t melt off secondary roads.

Cline reported from Baton Rouge, La., and Finley from Norfolk, Va.