September 2026 Ranks Among Hottest on Record Globally and in U.S.
NOAA reported that September 2026 ranked as Earth’s second-warmest September on record, behind 2023, while the United States had its hottest September. Record-high temperatures covered 16.7% of the planet’s land and ocean surfaces, the largest monthly footprint since records began in 1951. Global ocean temperatures were the warmest for any September, and 2026 was tracking among the hottest years on record.
NOAA’s NCEI said September 2026 was Earth’s second-warmest September, with NASA and Copernicus agreeing. Record warmth covered 16.7% of global land and ocean, exceeding May 2024’s 14.2% and marking the broadest monthly extent since 1951. No areas set record September cold.
Ocean surfaces had their warmest September; land ranked third. North America, Asia, and the Arctic saw their warmest September. The contiguous U.S. had its hottest September, with Kansas, Oklahoma, Missouri, Arkansas, and Illinois setting state records. January-September U.S. warmth was also the highest on record.
The exceptional September warmth, especially persistent nighttime heat, could increase heat-related health risks for older adults, outdoor workers, and low-income households without reliable cooling. It may also raise electricity demand, strain water and crop systems, and affect regions from the central U.S. to parts of Asia and the Arctic. If 2026 or 2027 approaches record annual warmth, communities and infrastructure may face prolonged pressure to adapt.