A significant and long-lasting heat wave is currently impacting over 100 million people across the United States, prompting widespread heat alerts (above). Unusual and intense heat and humidity have settled over the Middle Mississippi and Ohio Valleys and are expected to persist through early next week. The Heat Risk for much of the country is red, which is a major level of heat risk. There are even some areas of purple, which is the highest level of heat danger: Extreme. These locations need to limit time outdoors, stay hydrated, and check on your neighbors.

Highs are expected to climb into the upper 90s and may even touch 100 degrees in some areas. When combined with elevated humidity, the heat index could exceed 110 to 115 degrees, a level of heat that can be hazardous even for healthy individuals. These conditions are particularly dangerous for vulnerable populations such as the elderly, children, outdoor workers, and those without access to reliable air conditioning or hydration. 

What makes this heat wave especially troubling is its expected duration and the lack of overnight relief. Typically, cooler nighttime temperatures help the body recover from the daytime heat, but high humidity levels are keeping nighttime temperatures elevated, offering little reprieve. Temperatures only dropped down to 81 degrees on Thursday in Greenwood, MS breaking the old record.

This will be the last day for the heat alerts across the northeast. A cold front that will brings strong storms is moving through on Friday bring temperatures back into the 70s and 80s.

This will bring the potential for records across the northeast. Keep in mind the added moisture will still be around, so some of the feels like temperatures will reach the triple digits here too.

Stay weather-aware and take heat seriously.

SE Heat

Meanwhile, the heat is expanding across the Southeast and Mid-South, with the most persistent and dangerous conditions anticipated across the Southeast and the Tennessee Valley. Across the south, with the added humidity, "feels-like" temperatures will soar to the 110s for some. Widespread EXTREME heat impacts are expected by Sunday.

This prolonged exposure to heat increases the risk of heat-related illnesses such as heat exhaustion, heat stroke, and dehydration.

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