MINNEAPOLIS (AP) -- Runways at Minneapolis-St. Paul International Airport were temporarily closed as fast-falling snow from the latest winter storm tested plow drivers who tried to keep up.

MSP spokesman John Welbes says ``the rate of snowfall is the challenge.'' Forecasters expected snowfall rates of an inch per hour with accumulations of up to 10 inches.

Minneapolis and St. Paul schools are among the scores of districts in Minnesota, Wisconsin and elsewhere that canceled classes Wednesday.