Overview
- A strong high‑pressure heat dome will push warnings and advisories farther west beginning Tuesday, with inland highs near 110°F in the valleys and deserts and unusually warm overnight lows that limit nighttime cooling.
- Models and the National Weather Service say elevated nighttime temperatures will be 8 to 12 degrees above normal, increasing the risk of heat‑related illness for people without reliable cooling.
- Moisture from the Gulf and monsoonal flow is expected to return midweek, raising the chance of isolated to scattered thunderstorms that could produce heavy rain, localized flash flooding and gusty winds in parts of the Southwest and Gulf Coast.
- The Storm Prediction Center has flagged elevated severe‑storm risk in some areas later this week, and the National Hurricane Center is monitoring multiple tropical waves with roughly a 50% short‑term development chance that could boost regional humidity and storm potential.
- Compounding hazards include Red Flag fire warnings and very high fire danger in parts of Washington, Saharan dust reducing air quality in South Florida, and likely strain on electricity and public‑health services if high temperatures persist.