Jackson Free Press

LINCOLN, Neb. (AP) — An unusual, late-summer heat wave has enveloped much of the Midwest, putting schools and sports events on hold.

Schools in Iowa, Nebraska, Wisconsin, the Dakotas and Illinois let out early on Monday as temperatures crept toward the mid-90s — beyond in some places. After-school sports practices and evening games were canceled in St. Paul, Minn., and misting stations were keeping people cool at the Minnesota State Fair, where about 90 fairgoers had been treated for heat-related illnesses over the weekend.

The heat wave is supposed to last through much of the week, the National Weather Service said. Heat of this magnitude is unusual for this time of year, but not unprecedented. In Des Moines, Iowa, for instance, temperatures on Aug. 26 have reached at least 100 degrees at least six times since 1881.

School districts took precautions, not wanting to put students and teachers in sweaty — and possibly dangerous — situations.

In central Iowa, Marshalltown Community School District administrators canceled afternoon preschool classes on Monday and Tuesday and were planning to release other students two hours early. Parts of all 10 of district buildings have air conditioning, but some rooms aren't connected.

"The buildings can heat up pretty fast, especially when you have kids in there," district spokesman Jason Staker said. "It's not a good environment for students or teachers."

Five elementary schools in Fargo, North Dakota, canceled classes through Wednesday because the buildings weren't fully air-conditioned. Temperatures inside them on Sunday ranged from 85 degrees to 90 degrees, Fargo Schools Superintendent Jeff Schatz said.

In South Dakota, the Sioux Falls School District continued with classes as scheduled, but spokeswoman DeeAnn Konrad said teachers kept window blinds closed and turned off lights in classrooms. The district was also prepared to move students into cooler rooms at nearby churches and a Christian school, she said.

School administrators in the western Nebraska town of Alliance decided to send students home early after local forecasters predicted temperatures in excess of 90 degrees. Some classes in the 1,600-student district are held on the third floor, and temperatures rise when students fill the room.

"It can get uncomfortable even when the temperatures are in the upper 80s," superintendent Troy Unzicker said.

Minneapolis students had to go to school all day, but administrators canceled after-school activities and distributed 750 cases of water to schools. Officials also sent industrial fans to the 18 buildings that lack air conditioning, district spokeswoman Rachel Hicks said. Parents were advised to dress their kids in light clothing, while staffers watched for any symptoms of heat-related illnesses.

In Des Moines, organizers of a downtown farmers market set for Wednesday postponed the event out concern over the extreme heat

The Iowa Department of Public Health issued a statewide advisory for vulnerable populations, including young children and the elderly. In some cases, the heat can become so extreme that sweating isn't enough for people to lower their body temperatures, Dr. Patricia Quinlisk said.

"Especially when the humidity is high, sweat will not evaporate as quickly, preventing the body from releasing heat quickly," she said.