Map Shows Millions Facing 'Lethal' Heat Warning in 7 States

A National Weather Service map showing where heat warnings have been issued in pink.

Excessive heat warnings have been issued for seven states expecting "lethal" temperatures.

The summer has already been characterized by extreme heat, with the southwest experiencing a heat wave at the beginning of this month, before it shifted to the Midwest, Northeast and eventually the Plains.

Now, the National Weather Service is forecasting "rare, long-duration extreme heat with little to no overnight relief" for multiple areas in Texas, Oklahoma, Louisiana, Tennessee, Arkansas, California and Mississippi.

An alert that applies to much of central California, including the city of Selma and Yosemite Valley, said people in these places can expect "dangerously hot conditions with a 75 percent Probability of high temperatures 105 or hotter."

This warning has been in place since 11 a.m. on Tuesday and is set to last until 8 p.m. Pacific Time on Saturday.

A new alert has been issued for places in Arkansas, from 10 a.m. to 8 p.m. Central Time on Saturday, with "dangerously hot conditions with heat index values up to 110 degrees or greater" expected.

The warning applies to portions of central, eastern, north-central, southeast, southwest and western Arkansas, including Havana, Newport and Hot Springs.

An almost identical warning is in place for parts of east Arkansas and north Mississippi, where heat index values up to 112 are forecast.

It covers the cities of Paragould, Wynne, Jonesboro, Helena-West Helena, Harrisburg, Charleston, Forrest City, Batesville, Marks, Tunica, Corning, Clarksdale, Piggott and Marianna.

In parts of north Mississippi, southeast Missouri and west Tennessee, heat index temperatures of 110 degrees are set to hit between 11 a.m. and 8 p.m. CT on Saturday.

Many of these states are also covered by further warnings, including one issued by the NWS in Shreveport, Louisiana.

This warning also applies to portions of south-central and southwest Arkansas, north-central and northwest Louisiana, southeast Oklahoma, and east and northeast Texas.

The NWS in Tulsa, Oklahoma, has issued its own alert for Arkansas, Crawford, Franklin and Sebastian Counties—in place from noon until 9 p.m. CT.

Central Texas—including the cities of Cleburne, Weatherford and Sherman—is also covered by a separate warning issued by the NWS in Fort Worth.

All warnings give similar advice on how to handle the excessive heat. Little Rock's NWS said: "Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.

"Take extra precautions when outside. Wear lightweight and loose-fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke."

The Fort Worth NWS added: "To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air-conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 911."

The NWS' Climate Prediction Center has already predicted that at least a dozen states will experience above-average temperatures over the Fourth of July, with people warned by their local forecasters "to keep an eye on the forecast as it evolves."

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