A major heat wave is expected to affect the US Midwest and East Coast during Fourth of July week. Temperatures will soar, with blistering hot temperatures and oppressive humidity posing a danger for millions from the Plains to the East Coast. At least 230 million people could be exposed to extreme heat that could lead to health issues.
In the Midwest, the heat will intensify this weekend and spread into the region through much of the week. Places like Milwaukee, Chicago, St. Louis, and Minneapolis can expect triple-digit temperatures, making conditions downright dangerous for long periods. Daily record highs are possible by the middle of the week, especially in the Ohio Valley.
In the East, hotter air will arrive on Monday, and it will last for much of the week. Highs in the mid-upper 90s will be common, with some triple-digit highs possible in the mid-Atlantic. Dangerous heat indices from 100 to 110 degrees are expected in areas such as Washington, D.C., Philadelphia, and Richmond, Virginia.
The South will experience persistent and oppressive heat, with highs in the 90s through this week. Some locations could top 100 degrees, especially in Texas and the Carolinas. Daily high temperature records could fall in the region.
While there is still some uncertainty about how long the heat wave will last, computer models suggest it could retreat westward into the High Plains by the holiday weekend. This could bring relief to the East Coast, especially New England, by then. However, it’s essential to stay tuned for updates and check back frequently for the latest forecast.
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Source: https://weather.com/2026/06/24/forecast/national/heat-wave-fourth-of-july-week-midwest-south-east