Heat will remain hot in the headlines across much of the nation this week. The large heat dome affecting much of the southern U.S. will not let up soon. In fact, it is going to grow its reach.

A good portion of the country will see dangerous heat take hold this week, as a stubborn heat dome in the South expands farther north and east.

Sweltering temperatures and heat index values will first stretch across the Mississippi River Valley and Midwest on Monday and Tuesday before extending up the Eastern Seaboard through the second half of the week.

The heat will intensify even more throughout the Southwest at the start of the workweek, where highs reaching into the 100s will span across Southern California’s inland valleys and high deserts through Texas and portions of the southern Plains.

Farther east, temperatures will warm well into the 90s across much of the Deep South and Southeast, but heat index values will still reach near and into the triple digits all week.

By the middle to latter part of the week, 90-degree temperatures will dominate across much of the eastern two-thirds of the country.

Parts of the Northeast could see high temperatures break or tie records on Thursday and Friday.

Parts of Florida, Texas and the Plains are under a Heat Advisory through at least Tuesday evening, with Excessive Heat Warnings still in effect for parts of southern Arizona and California.

Additional heat alerts will likely go in effect as the heat expands farther north and east this week.

Regardless, the combo of hot temperatures and high humidity will increase the threat of heat-related illnesses, such as heat exhaustion and heat stroke.

(National Weather Service)

To stay safe, keep hydrated, avoid strenuous outdoor activities and stay in air-conditioned rooms or shaded areas during the peak heating hours of the day. Dressing in light, loose-fitting clothes will also help keep body core temperature regulated.

In addition, keep a close eye on children, pets and older adults in the days ahead.

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