Overview
- The Weather Prediction Center has placed large parts of the Southern Plains, Mississippi Valley and Southeast under Major‑to‑Extreme heat risk, with heat‑index values expected to reach 105–115°F and isolated Desert Southwest highs forecast near 115–120°F.
- The Storm Prediction Center put portions of the Upper Midwest in an Enhanced severe risk for damaging winds, large hail and isolated tornadoes, and recent outbreaks there knocked out power for hundreds of thousands and forced major flight and rail disruptions.
- A Moderate risk of excessive rainfall has been issued for the New York City tri‑state area as an unusually strong upper‑level low deepens, with training thunderstorms Tuesday night–Wednesday capable of producing up to 2 inches per hour and rapid urban flash flooding.
- Monsoonal moisture will keep daily heavy afternoon storms active across the Four Corners and Southwest, raising flash‑flood danger near burn scars, slot canyons and steep terrain and prompting local advisories.
- Forecasters expect a brief midweek cooldown behind a passing cold front before the heat dome shifts west later in the week, which could push record or near‑record temperatures into parts of the Desert Southwest and California this weekend; tens to hundreds of millions of people are already under heat alerts and infrastructure is under strain.