Updated

Officials in Greensboro, N.C., said one person was killed Sunday after a tornado struck the city, part of a severe storm system that also dumped two feet of snow on parts of the Upper Midwest and knocked out power to hundreds of thousands.

Greensboro police gave no immediate details about the death. However, Fox 8 reported that the victim was a motorist who was hit by a falling tree. Authorities declared a state of emergency in the city after high winds reportedly damaged at least seven homes and destroyed one mobile classroom.

About 75,000 homes and businesses were without power late Sunday afternoon in the Carolinas. Duke Energy said about 43,000 customers lacked power in North Carolina, and another 9,000 in South Carolina. South Carolina Electric and Gas Company reported 23,000 customers without power in South Carolina.

The airport in Charlotte said on Twitter Sunday that severe weather briefly caused a ground stop and forced air traffic controllers to leave their tower. The ground stop was later lifted.

The Greensboro death is at least the fourth to be blamed on the storm system which has stretched from the Gulf Coast to the Great Lakes.

A sleeping 2-year-old girl in Louisiana was killed when a tree fell on her family's recreational vehicle early Saturday. A Wisconsin woman was killed when she lost control of her minivan on slick roads and veered into an oncoming SUV. And an Idaho truck driver was killed when his semitrailer struck a semi in western Nebraska that had been stranded on a highway by the bad weather.

Minnesota storm 720

A Delta Airlines flight attendant negotiates the snowy streets of Minneapolis, Minn. Saturday afternoon. (Anthony Souffle/Star Tribune via AP)

At Minneapolis-St. Paul International Airport, where more than 13 inches of snow had fallen, 230 flights were canceled Sunday. Two runways were open, but winds were still strong and planes were being de-iced, spokesman Patrick Hogan said. On Saturday, the storm caused the cancellation of nearly 470 flights at the airport.

The wintry grip on the Twin Cities continued to keep the boys of summer off the diamond, forcing the postponement of the third straight Minnesota Twins-Chicago White Sox game. The New Yankees and the Tigers were rained out Saturday in Detroit and had planned to play a doubleheader on Sunday, but those games also were postponed. The Los Angeles Angels at Kansas City Royals, Atlanta Braves at Chicago Cubs and Toronto Blue Jays at Cleveland Indians games also were rained out Sunday.

The prolonged wintry weather is "starting to beat everybody down," said Erik Ordal, who lives in downtown Minneapolis and was taking his 3-month-old golden retriever puppy, Dakota, out for a walk in the snow. Ordal, who grew up in South Dakota, said he is used to the cold, snowy weather "but I'm certainly ready for some warmth."

Two northeastern Wisconsin communities, Tigerton and Big Falls, received more than two feet of snow over the weekend, the National Weather Service in Green Bay reported. Parts of the state that were already blanketed were getting a second helping of snow on Sunday. The heavy snow caused part of a hotel roof to collapse over a pool at a hotel in Ashwaubenon, which is next to Green Bay, but no one was in the pool area at the time, and no one was hurt.

The storm finally let up in South Dakota, allowing the airport in the state's largest city, Sioux Falls, to reopen for the first time since Thursday. Interstates 90 and 29 in parts of eastern South Dakota also reopened, and no-travel advisories were lifted across the state border in southwestern Minnesota.

In Michigan, freezing rain that began falling overnight had left roads treacherous and cut power to hundreds of thousands of homes and businesses by midday Sunday even as heavy snow was forecast to dump a foot or more of snow on parts of the state's Upper Peninsula by early Monday.

The storm system prompted Enbridge Energy to temporarily shutter twin oil and gas pipelines in Michigan that may have been recently damaged by a ship anchor strike.

The Line 5 pipelines were temporarily shuttered Sunday afternoon due to a power outage at Enbridge's terminal in Superior, Wisconsin, Enbridge spokesman Ryan Duffy told The Detroit News.

Enbridge decided to shut down the twin pipelines until weather conditions improve in the Straits of Mackinac, which links Lake Huron and Lake Michigan, Duffy said.

In Arkansas, a tornado ripped through the tiny Ozark Mountain town of Mountainburg on Friday, injuring at least four people. In Texas, hail the size of hen eggs fell south of Dallas, according to meteorologist Patricia Sanchez.

And another round of snow is possible midweek in the Upper Midwest, said meteorologist Eric Ahasic at the National Weather Service in Chanhassen, Minn.

"It's not going to be as much snow as this one, thankfully," Ahasic said.

The Associated Press contributed to this report.