(AP/KTTS) — More than 100 million Americans are being warned to stay indoors if possible as a heat wave settles over states stretching through parts of the Gulf Coast to the Great Lakes and east to the Carolinas.

There is a Heat Advisory until 8 p.m. for counties north of Springfield.

Heat index readings will be close to 100 degrees again today.

Another Heat Advisory is in effect central and south central Missouri for today. Heat index values will once again exceed 100 degrees in the advised area. Heat index values in the middle to upper 90s are expected in counties not in the advisory area. #mowx #kswx pic.twitter.com/7x5UWjwdX3

— NWS Springfield (@NWSSpringfield) June 14, 2022

The National Weather Service Prediction Center in College Park, Maryland, said Monday that a combination of heat advisories, excessive heat warnings and excessive heat watches will impact 107.5 million people, and record-setting temperatures are expected to last through midweek.

St. Louis, Memphis, Minneapolis and Tulsa are among several cities under excessive heat warnings, with temperatures expected to reach above 100 in some areas.

High humidity is forecast to accompany the heat, adding to the dangerous conditions.