More than 140 million people in the Midwest and Southeast were warned of dangerously high temperatures Tuesday as one of the biggest heatwaves in years swept across more than a dozen states.
The heat that has lasted for days is expected to worsen over the course of the week, the National Weather Service said in a statement Tuesday update. Hot weather is to be expected at this time of year, the agency said, but the upcoming days of “scorching” triple-digit temperatures combined with “brutal humidity” would be hotter than 120 degrees in some locations.
“While it is not uncommon for August to see dangerous heat, these temperatures are extremely unusual and are likely to break numerous daily and possibly monthly records,” the NWS said. “In fact, highs are forecast to be as much as 20 degrees above average across Iowa and neighboring states over the next few days.”
Warnings are currently in place in 17 states across the Midwest and as far south as the Southeast, ranging from heat warnings to excessive heat warnings. More than 40% of the US population resides within the advisory and warning zones.
Several major cities are subject to heat warnings, including Chicago, St. Louis, Minneapolis, Kansas City, Nashville, Oklahoma City, Louisville, Dallas, Houston and New Orleans.
That’s what the NWS predicts More than 90 record high temperatures will be broken in the next three days.
The agency’s Greater Chicago branch warned On Tuesday afternoon, heat indices, which reflect how hot it actually feels when both air temperature and humidity are factored in, are expected to rise to as high as 115 degrees over the following two days.
The NWS for the St. Louis region, which has been grappling with dangerously hot weather for days, said the rare high temperatures were already being recorded.
“We’re only halfway through this heat wave, but it’s already one for the record books,” the agency said tweeted. “We’ve ONLY seen a 115F heat index for 14 days and one of those was this Sunday.”
The Kansas City-area NWS bureau urged people to limit outdoor exposure as much as possible, saying the conditions were “untenable Wear light colors even for short periods and when outdoors as they absorb less heat.
People shouldn’t expect much respite from the heat at sunset.
“Very warm overnight temperatures, falling only into the upper 70s and below 80s, will amplify the impact of this potentially deadly heat wave,” the NWS warned.
Extreme heat waves, which deprive the body of fluids and compromise the functioning of kidneys and other vital organs, are the deadliest weather-related events. Most years they are kill more Americans as hurricanes, floods and tornadoes combined.
This week’s high temperature event is due to a high pressure ridge, or “heat dome,” located over the affected region, trapping hot air.
Last month was by far the hottest month on record, European scientists reported earlier this month with a dire warning about the climate crisis. Scientists have found that climate change is causing heat waves 150 times more likely.