15 Million People are Under Extreme Heat Warnings This Weekend

A massive heat wave is sweeping across the Central Midwest and parts of the South, pushing temperatures into the upper 90s and even triple digits. When accounting for humidity, many of the impacted areas will feel even hotter, often by 10 degrees or more. As of Thursday, August 13th, the National Weather Service had standing extreme heat warnings for more than 260 counties across 10 states. 

Heat is the leading climate-related cause of death in the United States, and the NWS only issues extreme heat warnings when high temperatures “pose a significant threat to life.” For the 15.1 million Americans currently under an extreme heat warning, the NWS advises avoiding outdoor activities, remaining in air conditioned or shaded areas as much as possible, and staying well hydrated. 

In many of the impacted counties, dangerous heat is expected to last into the weekend, as temperatures are forecasted to be well above normal between Friday and Saturday. 

Using data from the National Oceanic and Atmospheric Administration, Climate Crisis 247 identified the states where the most people are under an extreme heat warning. We ranked all states on the share of the population living in a county with a standing heat warning as of August 13th. We also reviewed weekend forecasts in all counties with available data from NOAA’s Southeast Regional Climate Center, and identified the county with a standing heat warning where temperatures are expected to be highest between Friday, August 14th, and Sunday, August 16th. 

10. Mississippi

• Share of population under extreme heat warning: 1.6% (47,553 people)
• Number of counties under extreme heat warning: 4 out of 82 Mississippi counties
• Extreme heat warning county with the highest forecasted weekend temperature: Tunica County
• Highest expected temperature in Tunica County: 104.0°F on Sunday, August 16 in Tunica, MS

9. Indiana

• Share of population under extreme heat warning: 4.8% (335,603 people)
• Number of counties under extreme heat warning: 6 out of 92 Indiana counties
• Extreme heat warning county with the highest forecasted weekend temperature: Vanderburgh County
• Highest expected temperature in Vanderburgh County: 97.1°F on Sunday, August 16 in Evansville, IN (8.9°F above normal)

8. Georgia

• Share of population under extreme heat warning: 7.2% (806,382 people)
• Number of counties under extreme heat warning: 12 out of 159 Georgia counties
• Extreme heat warning county with the highest forecasted weekend temperature: Chatham County
• Highest expected temperature in Chatham County: 100.0°F on Friday, August 14 in Savannah, GA (8.9°F above normal)

7. Illinois

• Share of population under extreme heat warning: 7.8% (992,265 people)
• Number of counties under extreme heat warning: 25 out of 102 Illinois counties
• Extreme heat warning county with the highest forecasted weekend temperature: St. Clair County
• Highest expected temperature in St. Clair County: 97.0°F on Saturday, August 15 in Belleville, IL

6. Kentucky

• Share of population under extreme heat warning: 13.0% (594,532 people)
• Number of counties under extreme heat warning: 22 out of 120 Kentucky counties
• Extreme heat warning county with the highest forecasted weekend temperature: McCracken County
• Highest expected temperature in McCracken County: 99.1°F on Sunday, August 16 in Paducah, KY (9.3°F above normal)

5. South Carolina

• Share of population under extreme heat warning: 21.6% (1,183,570 people)
• Number of counties under extreme heat warning: 8 out of 46 South Carolina counties
• Extreme heat warning county with the highest forecasted weekend temperature: Charleston County
• Highest expected temperature in Charleston County: 99.1°F on Friday, August 14 in North Charleston, SC (8.9°F above normal)

4. Oklahoma

• Share of population under extreme heat warning: 38.7% (1,585,324 people)
• Number of counties under extreme heat warning: 24 out of 77 Oklahoma counties
• Extreme heat warning county with the highest forecasted weekend temperature: Tulsa County
• Highest expected temperature in Tulsa County: 105.0°F on Sunday, August 16 in Tulsa, OK (11.6°F above normal)

3. Arkansas

• Share of population under extreme heat warning: 38.8% (1,197,534 people)
• Number of counties under extreme heat warning: 25 out of 75 Arkansas counties
• Extreme heat warning county with the highest forecasted weekend temperature: Pulaski County
• Highest expected temperature in Pulaski County: 101.9°F on Friday, August 14 in Fort Smith, AR (7.6°F above normal)

2. Kansas

• Share of population under extreme heat warning: 88.9% (2,641,840 people)
• Number of counties under extreme heat warning: 56 out of 105 Kansas counties
• Extreme heat warning county with the highest forecasted weekend temperature: Sedgwick County
• Highest expected temperature in Sedgwick County: 101.9°F on Saturday, August 15 in Wichita, KS (10.5°F above normal)

1. Missouri

• Share of population under extreme heat warning: 91.5% (5,715,469 people)
• Number of counties under extreme heat warning: 83 out of 115 Missouri counties
• Extreme heat warning county with the highest forecasted weekend temperature: Greene County
• Highest expected temperature in Greene County: 99.1°F on Sunday, August 16 in Springfield, MO (9.6°F above normal)