Three Heat Waves Hit the US in July — More May Come

July 2026 brought three US heat waves. On July 3, 185 million people faced heat alerts. Another struck the Southwest and Great Plains mid-month. A third trapped 40 million under a "heat dome" — a mass of hot air that stays put. America saw its second-hottest start to any year on record. Forecasters expect a short break before heat may return by the August 1–2 weekend.