Overview
- A large heat dome has broadened over the central United States, and roughly 70 million people are under National Weather Service heat advisories as of Saturday, July 25.
- Daytime highs will commonly reach the upper 90s to low 100s with heat‑index values often between 105°F and 115°F and isolated desert spots forecast to climb higher.
- Local extreme heat warnings and advisories cover hotspots including Southwest deserts and Palm Springs, parts of Southern California, the Colorado Front Range and areas of the Plains and Nebraska.
- Health officials and local governments are opening cooling centers, urging hydration and reduced outdoor activity for children, the elderly and people with health conditions because overnight lows will stay unusually warm.
- Forecasters say humidity will rise late Sunday into early next week, increasing the chance of scattered to organized storms with risks of damaging winds, large hail and heavy rain, and the UK also has active heat‑health alerts with a possible fourth heatwave next week.