Dangerously high temperatures hit Midwest, excessive heat warning issued for Chicago

Thirty-eight million people are under heat alert Monday as dangerously high temperatures are expected to hit the Midwest.

An excessive heat warning has been issued in Chicago, where the heat index (the temperature felt with humidity) could reach a scorching 110 degrees Monday and Tuesday.

Minneapolis, Madison, Wisconsin, and Omaha, Nebraska, are also under excessive heat warnings. The heat index could reach 115 degrees in those cities on Monday.

In Detroit, public schools will close three hours early Monday and Tuesday due to the heat.

Heat will spread east and south throughout the week. Record highs are possible from Chicago to Louisville, Ky., on Tuesday, and from Nashville, Tenn., to Washington, D.C., on Wednesday.

The numbers come on the heels of record temperatures in Texas over the weekend. Amarillo hit a record 104 degrees on Sunday.

According to CDC WONDER, an online database, hundreds of deaths occur each year in the United States due to excessive heat, and scientists warn that the true number of heat-related deaths is likely higher.

Click here for tips on how to stay safe in the heat.