Heat Wave Grips Midwest, Northeast And South To End Workweek

 Chris Dolce and Jonathan Erdman

Published: July 26, 2023

A​ heat wave will grip the Midwest, Northeast and South to end the workweek after shattering records in the Southwest much of this month.

T​his persistent excessive heat has been camped over the nation's southern tier from the Desert Southwest to Florida much of this month. It's been the hottest start to July on record in Phoenix, Baton Rouge and Miami.

Now that heat is engulfing the northern tier over the coming days. Highs will surge toward 100 degrees in some Midwest cities and well into the 90s in the Northeast.

Heat alerts are in effect for tens of millions of people. The National Weather Service (NWS) has issued heat advisories and excessive heat warnings in the Northeast, Midwest, Plains and Southwest. That means outdoor activities should be limited in these areas right now and in the coming days because of the possibility of heat-related illnesses.

Heat spreads to Midwest, Northeast this week. After biding time in a rather cool pattern for mid-July, a heat wave has arrived in the Midwest.

Highs ranging from the middle 90s to near 100 degrees are possible in the Plains and Midwest, from Kansas and Missouri to as far north as the Dakotas, southern Minnesota and Iowa over the next few days. Chicago could see highs reach the middle 90s at times through Friday.

(​MAPS: 10-Day U.S. Forecast Highs And Lows)

The Northeast is also facing increasing temperatures and humidity through the end of the week.

H​ighs will jump into the middle to upper 90s from New York City to Washington, D.C., for a time as the week comes to a close. Hartford, Connecticut, New York City and Washington, D.C., will come within a few degrees of their daily record highs on Friday.

Increasing humidity will make the heat feel even worse in some areas. The heat index could peak near or over 100 degrees in portions of the mid-Atlantic and Midwest at times through the end of the week.

H​eat relief arrives for some by this weekend. Fortunately, the upper Midwest and Northeast will see temperatures tumble from a sweeping cold front passing through those regions Friday through Sunday. Highs could drop back into the low 80s and upper 70s from Minneapolis to Chicago and New York.

T​he Deep South will also swelter into the weekend. Highs ranging from the middle to upper 90s to near 100 degrees will be common across the South over the next several days, from Texas and Oklahoma to the Carolinas. Heat index temperatures will easily climb over 100 degrees in the afternoon.

B​e sure to take heat precautions if you have any outdoor plans in the region over the coming days.

S​outhwest heat records shattered, but some modest cooling coming soon. Even by Desert Southwest standards, this heat wave has been record-smashing. You can find a full recap of all the records set this month at this link.

That searing heat will continue to affect the Southwest and Great Basin to end this week, but temperatures will begin to lower back closer to average for this time of year by early next week.

Here's how to stay safe: The hot conditions will be particularly dangerous for vulnerable groups, such as the sick and the elderly. The NWS has useful heat safety tips that can be incorporated into a daily routine when extreme heat sets in:

-Job sites: Stay hydrated and take breaks inside as often as possible.

-Indoors: Check on the elderly, sick and those without air conditioning.

-In vehicles: Never leave children or pets unattended – look before you lock.

-Outdoors: Limit strenuous activities and find shade. Drink plenty of water and avoid alcohol.

(MORE: 4 Things Extreme Heat Can Do To Your Body)

Here's why the heat has expanded: A strong area of high pressure in the upper atmosphere is the main culprit in this heat wave. The high causes air to sink toward the ground, which compresses the air and makes it even warmer.

I​n this case, the heat dome has expanded from the Southwest into the Plains. At the same time, another hot dome of high pressure will build across the western Atlantic into the eastern states.

The result is excessive heat spreading across a wide area from the Plains to the Midwest, Northeast and South.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.