It was so cold yesterday in the Upper Midwest, and visibility was so poor in blowing snow, that church services were called off in parts of Michigan. At noon, thermometers in one North Dakota town still registered only 20 below zero.

The windy, bitterly cold weather blanketed a region from the Dakotas across much of Minnesota into Wisconsin and Michigan. Subzero temperatures at midday extended into northern Iowa, the National Weather Service said.

Snow whipped up by the bitingly cold wind created hazardous driving conditions yesterday in Michigan. State Police said the 5-mile-long Mackinac Bridge was closed because of whiteout conditions, and the sheriff’s office in southwest Michigan’s Cass County said visibility was less than 20 feet.

Churches across western Michigan canceled services, the Grand Rapids Press reported.

“The road conditions are just terrible. There’s been slide-offs all over and the roads are very icy,” a weather service meteorologist in Grand Rapids, William Marino, said.

Snow drifts also closed some roads in Wisconsin and Michigan, police said.

Yesterday’s Lansing Polar Plunge charity benefit, in which people were to jump into the cold water at Hawk Island County Park, was reset to February 24, the Lansing State Journal reported.

Yesterday’s midday temperature there was only zero, but the wind chill was 23 below zero, the weather service said.

However, the weather couldn’t keep Wisconsin sturgeon spearers away from frozen lakes yesterday, the second day of the state’s spearing season.

Terry Gerhartz, of Chilton, Wis., said he made sure not to have any exposed skin when he went to his fish shanty on Lake Winnebago. “If you got stuck out there, you’d get cold in a hurry,” Mr. Gerhartz, 48, said as he warmed up at a restaurant in Hilbert.

Yesterday’s noon reading at Devils Lake, N.D., was 20 below, with a wind chill of minus 38, the weather service said. On Saturday, the town warmed to a high of 13 below — with a wind chill of minus 42.