NOAA: Summer 2026 Becomes Hottest on Record Across the Contiguous U.S.

NOAA says meteorological summer (June–August) 2026 was the hottest on record for the contiguous United States, averaging 74.4°F (3.0°F above the 20th‑century average). The heat was broad across the Lower 48, with four states—Colorado, Utah, Arizona, and New Mexico—posting their own summer records, and July’s heat dome driving 100°F+ days and persistently hot nights; the period also saw above‑average minimum temperatures in 17 states and contributed to drought strains in the Colorado River Basin, including record low levels at Lake Powell and Lake Mead.