Dangerous heat is gripping parts of the United States, with more than 42 million people under heat alerts across much of the South. Temperatures in some cities have climbed above 100°F, while a high of 119°F was recorded Wednesday at a weather station about 16 miles southwest of Tecopa, Calif., the National Weather Service said.
The “heat dome” that brought extreme heat to much of the central and eastern U.S. has shifted west, with very high temperatures expected to persist across the South through Saturday before spreading into the Southwest, Intermountain West and northern High Plains over the weekend.
Extreme heat warnings are in effect across much of the Southwest, including parts of Arizona, California, Nevada and southern Utah, where dangerously warm weather is expected through the weekend.
Most warnings are in effect from Thursday through Sunday, although parts of California’s Mojave Desert remain under an extreme heat warning through Monday night. Highs are forecast to range from around 100°F to as high as 120°F in some desert locations, with little prospect of overnight relief in many areas.
Warnings cover the Phoenix and Tucson metro areas, the lower elevations of the Grand Canyon, Las Vegas, Death Valley, Joshua Tree National Park, the Mojave and Coachella deserts, the Inland Empire and parts of the Los Angeles and San Diego regions. They are also in place in Zion National Park, Capitol Reef National Park and the Lake Powell area in Utah.
How hot will it feel, exactly?
A couple cool off by the fountain at the World War II Memorial amid a heat wave in Washington, D.C., on June 25. (Kevin Lamarque/Reuters)
(REUTERS / Reuters)
Heat index values, which indicate how hot it feels when humidity is taken into account, are forecast to reach as high as 120°F (49°C) in parts of southern Arizona and South Texas on Sunday.
Evening temperatures are anticipated to provide little relief, with overnight lows remaining in the upper 70s and low 80s across much of the Gulf Coast, while temperatures in desert cities stay well above 80°F.
According to the National Weather Service’s HeatRisk monitor, more than 2 million people across Arizona, New Mexico, Texas, Oklahoma, Louisiana, Mississippi, Alabama and the Florida Panhandle face the highest heat-risk level.
Another 24 million people across much of the southern Plains and Gulf Coast face a “major” risk, the second-highest level.
Such levels are “dangerous for anyone without adequate cooling or hydration,” the weather service warned, noting that the risk of heat-related illnesses increases significantly with prolonged exposure to extreme heat and humidity.
What you can do to protect yourself
Indianapolis Colts linebacker Segun Olubi cools off during practice at training camp in Westfield, Ind., on July 24. (Michael Conroy/AP)
(ASSOCIATED PRESS)
“Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors,” the NWS advised. “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.”
When will the heat wave break?
Some relief is on the way. According to the weather service’s long-range forecast, a strong cold front is expected to bring cooler temperatures to much of the eastern U.S. by next weekend, with much lower humidity and highs falling 10 to 20 degrees below this week’s levels.
Relief from the heat is “likely” by week’s end. (National Weather Service)