Heat wave weather forecast: Here's how hot it will feel, as 110 million face heat advisories

The heat index is heating up across the country as we approach the Fourth of July, pushing the mercury to dangerous levels in southern states ahead of the holiday.

Over 100 million people were facing excessive heat advisories throughout the country on Thursday, with heat indexes (how hot it feels with humidity factored in) over 115 degrees being recorded in parts of the U.S. by the Paste BN Heat Index.

With the heatwave blanketing southern U.S., here's what you can expect the weather to look like across the country this weekend.

Thursday forecast: 110 million in South under heat advisory as air-quality concerns linger in Midwest

Thursday, June 29

The highest heat index forecasts on Thursday are in Louisiana, Alabama and Mississippi, where the heat index could hit over 115 degrees across region.

On the East Coast, the heat index is expected to be around 70 to 75 degrees.

Parts of the west U.S. including Wyoming and Idaho can expect heat indexes from 70 to 90 degrees.

Friday, June 30

On Friday, the forecasted heat index remains steady across most parts of the U.S. In the southern part of the country, more states are expected to experience indexes of over 115 degrees, including Texas, Mississippi, Louisiana, Alabama and Arkansas.

Saturday, July 1

The heat index is expected to rise in parts of the country Saturday, with highs in the northern U.S. around 90 degrees. It will be less hot near the Gulf Coast, but southern Texas is expected to see an increase, with the heat index forecast to hit 115 degrees in some areas.

Sunday, July 2

Heat indexes are forecast to cool slightly in some southern states, with Mississippi, Alabama, and Louisiana expected to experience indexes between 105 to 110 degrees.

Parts of southern Texas and Florida could see indexes rise, however, with pockets forecast to have indexes of over 115 degrees.

Washington, Idaho, Colorado and Wyoming can expect heat indexes in the 70s and 80s, along with Pennsylvania, New York, Massachusetts, Vermont and Maine. A majority of the Midwest is expected to see indexes ranging from 80 to 95 degrees.

More: Chicago and Detroit have the worst air quality in the world due to Canadian wildfires. Here's how to stay safe.

Kate Perez covers breaking and trending news for Paste BN. You can reach her at kperez@gannett.com or on Twitter @katecperez_.