Millions of Americans under heat alerts Saturday as summer scorcher continues

Daytime highs across the nation's southern tier will reach into the 90s and lower 100s, with even higher heat indices approaching or exceeding 110 degrees, as they have done so for several days already this summer.

Numerous record-high temperatures will be reached this weekend as the southern region of the U.S. endures a hazardous heat wave that has baked the area for several weeks. 

The FOX Forecast Center said the dangerous temperatures will continue across parts of the central and southern Plains, Lower Mississippi Valley and the Gulf Coast as stubborn upper-level ridge remains anchored in place. 

Daytime highs reached into the 90s and lower 100s, with even higher heat indices approaching or exceeding 110 degrees, as they have done so for several days already this summer and will continue on Sunday.

These temperatures, along with exceptionally warm overnight lows near 80 degrees, will result in numerous records for both daytime highs and record-warm overnight lows. Widespread Heat Advisories and Excessive Heat Warnings are in effect.

The FOX Forecast Center said portions of the south-central Plains should cool off a bit by the weekend as a cold front is forecast to dip slightly farther south by then. On the other hand, the heat and humidity is forecast to extend farther east across the Southeast into the Carolinas through the middle of next week. 

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Despite a brief hiccup on Monday when the high only reached 108 degrees, the seemingly unending streak of 110-degree temperatures will likely continue over Phoenix where the hot ridge is forecast to expand across the entire southwestern U.S. this weekend.

Who will be under heat warnings and heat advisories?

Heat Advisories stretch from the Southwest through the Central Plains and Gulf Coast, with millions under an Excessive Heat Warning as temperatures soar and "feels-like" temperatures rise even higher through Monday evening. 

On Sunday, an estimated 49 million Americans may experience temperatures above 100 degrees. That number rises to 51 million by Monday before dipping to 46 million on Tuesday.

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Heat-related illnesses can set in within a matter of minutes, so officials all over the country have been warning residents to drink plenty of fluids and limit time outdoors to prevent heatstroke and heat exhaustion.

Unfortunately, the heat has become too much for many people to handle, as deaths caused by the heat have been reported across the country. Deaths include hikers inside California’s Death Valley National Park and children mistakenly left inside vehicles for hours under the summer sun.

In Arizona, at least 39 people have died in Maricopa County because of the heat, according to county officials.

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Pets, too, are at risk, and pet owners are being asked to keep an eye on their furry friends to make sure they're staying cool and safe. 

Even a police K9 in Louisiana died from a heat-related injury while trying to chase down suspects.