Dangerous heat slams Midwest and Gulf Coast: What to expect

Cities in the Midwest and the Gulf Coast could tie or break record high temperatures as dangerous heat slams the regions.

Excessive heat warnings are in effect for cities including Chicago, Minneapolis, St. Louis, Indianapolis and New Orleans.

On Wednesday, the heat index -- what the temperature feels like with humidity -- is forecast to soar to 104 degrees in Minneapolis, 112 in New Orleans and 113 in St. Louis.

New Orleans and Mobile, Alabama, could see record highs Wednesday afternoon.

In St. Louis, residents are forecast to see their hottest August day since 2013.

And in Chicago, the heat index reached 116 degrees on Wednesday, nearing the record of 118 degrees set in 1995.

The Dakotas and Minnesota will begin to see relief from the heat on Thursday, and the rest of the Upper Midwest, including Chicago, will cool down by Friday.

Then, the heat will shift its focus to the South. Some Gulf Coast cities could see their all-time hottest temperatures by the time the weekend arrives.