Overview
- A persistent upper-level ridge is driving extreme heat across wide swaths of the United States with heat-index values reaching about 110–115°F in the South and Southwest and desert highs forecast between 113 and 121°F.
- Las Vegas has recorded consecutive days above 110°F and forecasters say daily triple-digit readings are likely to continue through the coming weekend with a possible peak near 115°F.
- Forecasters issued multiple Heat Advisories and Extreme Heat Warnings for central Florida, the Southwest, California deserts and other regions while monsoonal moisture and stalled fronts are keeping humidity high and boosting flash-flood and severe thunderstorm risks in parts of the country.
- On Wednesday, the UKHSA placed amber heat-health alerts for southeast England and the Met Office warned of temperatures up to about 35°C as the Environment Agency declared drought in seven English areas, raising pressure on water supplies and fire services.
- Some areas should see short-lived relief later in the week as cold fronts push cooler air and higher rain chances into portions of the U.S. and U.K., but officials warn overnight warm lows and repeated heat pulses will keep health, power and wildfire risks elevated.