Oppressive summer heat grips large portions of U.S.

High temperatures and extreme humidity will extend into week of July 25

A heat wave and smog on the shoreline of Chicago Illinois.

A heat wave and smog on the shoreline of Chicago Illinois. (Image credit: iStock)

A widespread heatwave is parked over the central United States, causing heat index values to reach 110 degrees F, with some areas reaching 115 degrees by Sunday as the high pressure ridge spreads to the East.

As of Friday, July 22, almost 124 million people are under an Excessive Heat Warning, Excessive Heat Watch or Heat Advisory.

The high pressure and extreme humidity will begin to ease up on Tuesday, July 26, but some portions of the Southeast will continue experiencing heat index values as high as 110 degrees into Thursday.

A unique feature of this heatwave is its very high overnight lows, which will offer little relief from the oppressive heat – especially in the Northern Plains and Upper Midwest.

Beware of heat-related illnesses

Heat is a silent killer – people often don’t realize they are suffering from heat exhaustion until it’s too late. Learn how to cope with dangerous heat and take precautions to protect your health. Stay hydrated by drinking water, stay out of the sun, and schedule outdoor activities for early morning or evening hours. Heat stroke is a medical emergency, and if you see someone with the signs and symptoms, call 911 immediately. Please be sure to check in on elderly or sick friends and neighbors, too.

How hot will it get where you live?

Plug your Zip Code into the upper left hand window at www.weather.gov to access your local forecast.