MINNEAPOLIS — Fast-falling snow with accumulations of up to 10 inches closed scores of school districts in the Upper Midwest on Wednesday and delayed ground and air travel.

The National Weather Service issued a winter storm warning for much of central and southern Minnesota, through eastern South Dakota and into western Wisconsin.

Minneapolis and St. Paul schools are among the districts that canceled classes Wednesday. The weather service expected the Twin Cities to get anywhere from 6 to 10 inches of snow, which would assure a record total for any February since records have been kept.

Runways at Minneapolis-St. Paul International Airport were temporarily closed as accumulating snow tested plow drivers who tried to keep up. MSP spokesman John Welbes said “the rate of snowfall is the challenge.”

Among the larger Minnesota cities, New Ulm has 10 inches, Worthington 9 inches and Mankato 6 inches of snow. Gov. Tim Walz canceled his plans for an education visit to Moorhead on Wednesday because of tough travel conditions.

In Wisconsin, several dozen public school districts and private schools, mostly in the southwest, called off class Wednesday as commuters struggled with snow-covered and slippery roads.

In South Dakota, the Sioux Falls School District, where 7 inches of snow had fallen, delayed the start of classes, while other districts canceled school altogether. The South Dakota Department of Transportation’s travel map showed highways and interstates throughout the state as snow-covered and slippery.