A lion at the Henry Doorly Zoo in Omaha, Neb., licks a chunk of ice containing a frozen fish Thursday, as high temperatures and humidity affect much of the central U.S. Some cities have opened cooling stations for people and take other precautions.

CHICAGO — High temperatures and humidity is baking much of the central U.S. this week, making it feel as hot as 115 degrees in some places and leading some cities to open cooling stations and take other precautions.

The high pressure system, sometimes called a “heat dome,” will push conditions to their hottest point so far this summer, though record hot temperatures are not expected, according to the National Weather Service. Authorities from Minnesota to Louisiana are warning people to take precautions and check on the elderly and other vulnerable people.

The temperature in the South Dakota capital of Pierre reached 105 degrees Wednesday afternoon. Officials at the Canterbury Park track near Minneapolis canceled live horse racing on Thursday, when the heat index was expected to exceed 110 degrees.

Temperatures were forecast to reach the 90s for most areas of the central U.S. starting Wednesday and lasting into the weekend in some places. High humidity will make it feel anywhere from 105 to 115 degrees.