A massive heat wave has broken heat records in 14 states, including Arizona and California, reaching up to 112 degrees Fahrenheit in some areas.
Now it's creeping eastward, according to the National Weather Service.
The heat wave is continuing its journey through the Midwestern United States and is projected to affect anywhere from one-quarter to one-third of the 48 mainland states, National Weather Service meteorologist Gregg Gallina told The Associated Press.
The highest temperatures recorded today are in Arizona, New Mexico and Texas -- what the National Weather Service refers to as the Southern Rockies region.
But the hot air is on the move.
The reason these high temperatures persist is the "heat dome" phenomenon, in which high pressure prevents hot air from rising, trapping it in a bubble above a region.
As the dome of pressure moves, so too does the hot air -- and right now, it's barreling east.
The states that will be smothered by the heat dome in the coming days include those in the Southern and Central Plains regions.
This means residents of Texas, Colorado, Oklahoma, Kansas and Nebraska can expect to sweat as the heat blankets them on its eastbound journey.
What the heat dome means for climate change and our health According to Climate Central, the US has experienced rising blackout rates over the past 20 years, largely due to weather-related issues and an aging electrical grid.
As of August 2025, the US Environmental Protection Agency states that heat is the leading weather-related cause of death in the US.
The World Health Organization reports that between 2000 and 2019, about 489,000 heat-related deaths occurred each year.
Fortunately, humidity levels are not as high during a summer heat wave.
As humidity can contribute to dehydration, body strain and breathing difficulties,....
