Stifling Heat Dome Holds Central and Southern U.S. in Record‑Breaking Temperatures for a Second Day

For the second day in a row, a stubborn heat dome is draping the central and southern United States in sweltering conditions that feel almost unreal. Roughly 40 million people are now under extreme‑heat warnings, according to the National Weather Service.

Heat indexes north of 100 °F (38 °C) are stretching from Minnesota down through Mississippi, spilling westward into southern California and Nevada. In the desert Southwest, forecasters are even talking about scorching highs that could touch 120 °F (49 °C). It’s the kind of temperature you’d normally only expect in the deep summer of a few years ago.

Meteorologists say the culprit is a classic heat dome – a pocket of high pressure that traps warm air like a lid on a pot. "It’s extraordinarily hot," said Pete Miller, an outreach manager with the homeless‑services network Threshold CoC, who was handing out water bottles in Omaha, Nebraska. "We’re seeing a lot of people who are exhausted, drained by the heat in a way that is really dangerous. The humidity is insane. You stand outside for 30 seconds and you get drenched, and it’s going to be like that all night."

Some places are even setting new records. Rapid City, South Dakota, logged an all‑time high of 112 °F (44 °C) on Saturday. In Minnesota, a horse race at Canterbury Park in Shakopee was called off on Sunday because officials deemed the heat unsafe for both riders and animals.

Bob Oravec, a meteorologist with the NWS, explained that the core of the heat is shifting southward and will likely do so by early next week. Meanwhile, the moist air surrounding the dome is stirring up the potential for severe thunderstorms, flash flooding and hail around the Great Lakes. Those storm systems are expected to move eastward in the coming days.

Relief is forecasted to arrive briefly toward the middle of the week, but forecasters warn that another bout of blistering temperatures could return by the weekend. In other words, the heat isn’t going away anytime soon.

Public health officials are sounding the alarm, especially for children, older adults and anyone with pre‑existing medical conditions. The advice is simple but critical: stay in air‑conditioned spaces or cooling centers, drink plenty of water, and limit time in direct sunlight.

Adding to the broader picture, 2026’s first half has already been recorded as the second‑hottest on file for the continental United States, according to the National Centers for Environmental Information. That statistic underscores just how unusual and persistent this heat wave really is.