Dangerous heat wave grips Minnesota and much of the U.S.

Minnesota faced a NEXT Weather Alert on Monday, June 29, as the Twin Cities approached 100 degrees and heat index values neared 110. An extreme heat warning covered the metro and parts of central and southeastern Minnesota, while much of the rest of the state was under a heat advisory.

The danger was not confined to Minnesota. A long stretch of dangerous to record-breaking heat was building across the center of the nation and spreading eastward through the week, with humidity making the air feel even hotter ahead of the July Fourth holiday. Severe thunderstorms also remained a hazard in parts of the Plains and Midwest, adding another layer of risk for travelers and people working outdoors.

High heat and humidity can quickly trigger heat-related illness, and the National Weather Service counts heat as the deadliest weather phenomenon in the last 10 years. Anyone can suffer from heat illness, but people who live alone, have chronic medical problems or are otherwise vulnerable should be checked on by family, friends and neighbors. When heat index values are expected to exceed roughly 105 to 110 degrees for two consecutive days, many locations issue warnings that signal a serious threat to daily routines, outdoor labor and the demand for cooling.

A similar national heat wave hit in June 2025, when about 128 million Americans from Louisiana to Maine were under heat advisories. Boston reached 102 degrees and set daily records during that stretch.

In Minnesota, the worst of the heat was expected to linger into the Fourth of July period, keeping the state in a high-risk setup even after Monday’s alert.