State-by-State Lists Show Which Septembers Were Warmest in U.S. Records
The compilations use official NCEI monthly averages to show a recent clustering of extreme September heat that NOAA links to long-term warming with a strengthening El Niño raising the odds of more extremes.
Overview
- Stacker’s state-by-state rankings, which were republished by local outlets Sept. 3–4, use National Centers for Environmental Information monthly average temperatures to rank the hottest Septembers in each state since 1895.
- The lists name recent months near the top for many states, including Colorado’s September 2019, Texas’s September 2023, California’s September 2020, and Oregon’s September 2025 as each state’s hottest September on record.
- Each entry reports the statewide average temperature for the month and lists the statewide monthly high and low temperatures plus total precipitation for that September.
- Coverage places the compilations alongside NOAA findings from mid-2026 that noted tied warmest Julys, record-warm oceans, and a strengthening El Niño that raises the chance of further extreme heat into autumn and winter.
- The clustering of recent record months reinforces the long-term U.S. warming trend of about 0.14°F per decade and signals practical risks for communities, including higher heat exposure, greater demand on emergency services, and added strain on forecasting and observation systems.