Overview
- The upper‑level heat dome is forecast to produce the hottest days of the summer this weekend across the West, with dozens of record highs expected and more than 12 million people under Level 4 “extreme” heat risk.
- Local officials report growing human tolls, with Maricopa County confirming 40 heat‑related deaths so far this year and public health systems warned to expect surges in emergency visits.
- Separate storm systems are shifting severe thunderstorms into the middle Mississippi Valley, Ozarks, Upper Midwest and Ohio Valley and forecasters say slow storms could trigger damaging winds, hail, isolated tornadoes and localized flash flooding.
- The heat will worsen water and fire stress across the Colorado River basin where Lake Mead and Lake Powell sit at historic lows, increasing evaporation and heightening wildfire risk in drought‑stripped landscapes.
- U.K. authorities say half of England and all of Wales are officially in drought with nearly 2,900 heat‑associated deaths recorded in May–June and forecasters caution that short‑term rain will not reverse deficits before autumn rainfall is needed for recovery.