Parts of California, Nevada and Arizona faced dangerously high temperatures on Tuesday brought on by the first heat wave of the season, which is expected to remain until at least Friday evening.
Parts of California and Nevada could face temperatures above 110 degrees this week.
According to the National Integrated Heat Health Information System, at least 28 million people across the U.S. will remain under extreme heat warnings on Wednesday after nearly 40 million faced similar alerts a day earlier.
In its latest forecast for the next few days, the National Weather Service warned of temperatures above 100 degrees Fahrenheit in California's central valley, with the “heat risk”(a color-coded index for dangerously high temperatures) peaking on Wednesday.
Temperatures at Furnace Creek in California’s Death Valley—one of the hottest places in the country—crossed 112 degrees on Tuesday and could rise as high as 121 degrees on Thursday.
Temperatures above 110 degrees are expected to be common over the desert regions in California and Nevada—including Las Vegas.
Vegas could see the mercury topping 112 degrees Thursday, which the NWS says “would become the city's earliest observed 112 degrees on record.”
The agency said its excessive heat warnings and watches “extend from the central valley down through southern California's deserts, southern Nevada and southern/western Arizona.”
The NWS said it expects widespread temperature records to be tied or broken across the region where the heat wave has been forecast.
The extreme temperatures in the southwestern states and other parts of the country like Texas are the result of a “heat dome” that began moving towards the U.S. from Mexico earlier this week. Across the southern border, the heat dome triggered droughts and water shortages while claiming dozens of lives last month. According to the National Oceanic and Atmospheric Administration, a heat dome occurs when “a persistent region of high-pressure traps heat over a particular area, and it can linger for days to weeks.” A heat dome can prevent clouds from forming, resulting in an area receiving excess sunshine which can further boost temperatures, Accuweather says.
At least four migrants died after suffering heat strokes last weekend while trying to cross the southern border in El Paso, Texas, U.S. Customs and Border Protection officials said. Anthony Good, chief of Border Patrol El Paso sector, urged migrants to avoid crossing the border in the extreme weather: “The desert environment is extremely unforgiving, especially during the summer months…We urge anyone considering crossing illegally to understand the severe risks involved”
‘Heat Dome’ Expected Over California, Arizona And Other Western States This Week: What To Know (Forbes)