September is one of the warmer months of the year in Norman, with average highs near 30.4°C and lows around 18°C (mean 24.2°C). It is about average for rainfall, averaging 88 mm of rainfall and 61% relative humidity across the period.
September is one of the warmer months of the year in Norman. Across 45 years of records, the warmest September in Norman was 1998 — when the month averaged 28.9°C — while the coldest was 1989 at 20.4°C. Typical September days reach 30.4°C with nights near 18°C. The long-term trend is warming, about 0.5°C per decade.
September is about average for rainfall in Norman, averaging 88 mm of rainfall. The wettest September on record was 1991 with 212 mm, while the driest was 2004 at 26 mm.
Relative humidity in Norman during September averages 61%. The most humid Septembers were 2007 and 2018 at 79%, and the least humid was 2000 at 38%.
September receives about 5.1 kWh/m²/day of solar energy in Norman. The sunniest September was 2022 at 5.9 kWh/m²/day, and the cloudiest were 1986 and 2018 at 4.1.
Average wind speed in Norman during September is 2.9 m/s. The windiest Septembers were 1984 and 1985 at 3.7 m/s, while the calmest were 1990 and 2025 at 2.1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 23.5°C | 23.6°C | 23.7°C | 25.0°C | 25.5°C | +2°C |
| Avg High | 29.7°C | 29.7°C | 30.1°C | 31.0°C | 32.2°C | +2.5°C |
| Avg Low | 17.4°C | 17.4°C | 17.4°C | 19.1°C | 18.8°C | +1.4°C |
| Avg Rain | 103 mm | 116 mm | 67 mm | 89 mm | 52 mm | -51 mm |
September temperatures in Norman have risen by about 2°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 2.4°C (1989) to a record high of 44°C (1998).
Rainfall in September is about average for rainfall, averaging 88 mm, with a wettest year of 212 mm.
One of the best times to visit Norman
September is one of the best times to visit Norman. Expect days averaging 30.4°C and nights around 18°C (mean 24.2°C) — warmer than Norman's yearly average — with higher rainfall (88 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 31.1°C | 24.9°C | 18.7°C | 35.1°C | 14.6°C | 33 mm | 62% | 2.1 m/s | 5.1 |
| 2024 | 32.7°C | 25.6°C | 18.4°C | 38.7°C | 13.8°C | 42 mm | 53% | 2.3 m/s | 5.5 |
| 2023 | 34.5°C | 27.5°C | 20.6°C | 42.3°C | 16.0°C | 52 mm | 53% | 2.8 m/s | 5.3 |
| 2022 | 33.4°C | 26.3°C | 19.2°C | 37.3°C | 13.1°C | 31 mm | 50% | 2.7 m/s | 5.9 |
| 2021 | 33.8°C | 26.8°C | 19.7°C | 38.5°C | 11.7°C | 30 mm | 50% | 2.9 m/s | 5.7 |
| 2020 | 27.5°C | 21.9°C | 16.3°C | 32.9°C | 7.8°C | 123 mm | 76% | 2.5 m/s | 4.9 |
| 2019 | 32.4°C | 27.3°C | 22.2°C | 36.5°C | 19.7°C | 65 mm | 69% | 2.9 m/s | 5.4 |
| 2018 | 28.0°C | 23.5°C | 19.1°C | 35.8°C | 9.0°C | 210 mm | 79% | 2.6 m/s | 4.1 |
| 2017 | 30.2°C | 24.1°C | 18.1°C | 36.1°C | 12.0°C | 100 mm | 62% | 2.7 m/s | 5 |
| 2016 | 30.5°C | 25.0°C | 19.6°C | 35.8°C | 10.1°C | 111 mm | 67% | 2.8 m/s | 5.2 |
| 2015 | 31.3°C | 25.4°C | 19.6°C | 36.7°C | 14.1°C | 53 mm | 64% | 2.8 m/s | 5.4 |
| 2014 | 30.8°C | 24.8°C | 18.7°C | 37.3°C | 9.9°C | 47 mm | 62% | 3 m/s | 5.1 |
| 2013 | 32.6°C | 25.9°C | 19.2°C | 39.6°C | 9.5°C | 54 mm | 54% | 2.7 m/s | 5.4 |
| 2012 | 32.2°C | 25.4°C | 18.7°C | 41.0°C | 14.2°C | 94 mm | 52% | 2.8 m/s | 5 |
| 2011 | 31.6°C | 24.1°C | 16.5°C | 40.7°C | 10.5°C | 35 mm | 43% | 3.1 m/s | 5.6 |
| 2010 | 30.6°C | 24.8°C | 19.0°C | 36.2°C | 8.1°C | 126 mm | 67% | 3.2 m/s | 5.4 |
| 2009 | 27.9°C | 22.3°C | 16.8°C | 35.3°C | 9.6°C | 101 mm | 69% | 2.9 m/s | 4.3 |
| 2008 | 29.1°C | 22.8°C | 16.5°C | 33.7°C | 10.4°C | 39 mm | 66% | 2.7 m/s | 5.1 |
| 2007 | 28.3°C | 23.1°C | 17.9°C | 32.0°C | 12.2°C | 55 mm | 79% | 2.6 m/s | 4.9 |
| 2006 | 29.3°C | 22.5°C | 15.6°C | 35.1°C | 10.4°C | 72 mm | 53% | 2.9 m/s | 5.4 |
| 2005 | 32.7°C | 26.1°C | 19.5°C | 35.8°C | 11.6°C | 68 mm | 58% | 2.9 m/s | 5.7 |
| 2004 | 31.7°C | 25.0°C | 18.4°C | 37.7°C | 12.0°C | 26 mm | 53% | 3 m/s | 5.7 |
| 2003 | 28.2°C | 22.0°C | 15.9°C | 32.8°C | 9.6°C | 62 mm | 65% | 3 m/s | 4.8 |
| 2002 | 31.3°C | 24.7°C | 18.1°C | 36.8°C | 11.1°C | 74 mm | 56% | 2.7 m/s | 5.5 |
| 2001 | 28.3°C | 22.4°C | 16.5°C | 34.6°C | 7.0°C | 147 mm | 67% | 2.5 m/s | 5.1 |
| 2000 | 34.2°C | 26.5°C | 18.7°C | 43.5°C | 5.6°C | 27 mm | 38% | 3.2 m/s | 5.8 |
| 1999 | 29.8°C | 23.1°C | 16.3°C | 37.1°C | 7.6°C | 106 mm | 56% | 3.1 m/s | 4.8 |
| 1998 🔥 | 35.5°C | 28.9°C | 22.4°C | 44.0°C | 17.0°C | 68 mm | 53% | 2.9 m/s | 5.3 |
| 1997 | 32.5°C | 25.9°C | 19.3°C | 37.8°C | 12.1°C | 58 mm | 55% | 3 m/s | 4.9 |
| 1996 | 27.1°C | 21.3°C | 15.6°C | 32.5°C | 6.1°C | 130 mm | 72% | 2.4 m/s | 4.6 |
| 1995 | 28.2°C | 22.5°C | 16.8°C | 39.4°C | 4.2°C | 169 mm | 68% | 2.9 m/s | 4.3 |
| 1994 | 29.6°C | 23.0°C | 16.4°C | 35.2°C | 6.6°C | 75 mm | 60% | 2.8 m/s | 5 |
| 1993 | 28.4°C | 21.9°C | 15.4°C | 33.3°C | 6.3°C | 150 mm | 65% | 3 m/s | 5.3 |
| 1992 | 28.9°C | 22.7°C | 16.4°C | 33.1°C | 8.4°C | 70 mm | 69% | 3 m/s | 5.2 |
| 1991 🌧️ | 25.6°C | 20.9°C | 16.2°C | 31.9°C | 6.4°C | 212 mm | 77% | 2.6 m/s | 4.3 |
| 1990 | 31.5°C | 25.5°C | 19.5°C | 38.8°C | 8.7°C | 116 mm | 61% | 2.1 m/s | 5 |
| 1989 ❄️ | 26.4°C | 20.4°C | 14.4°C | 35.8°C | 2.4°C | 141 mm | 67% | 2.7 m/s | 5 |
| 1988 | 30.7°C | 23.8°C | 16.9°C | 37.7°C | 9.5°C | 160 mm | 59% | 2.7 m/s | 5 |
| 1987 | 28.9°C | 22.5°C | 16.0°C | 34.0°C | 8.9°C | 126 mm | 65% | 2.4 m/s | 5.1 |
| 1986 | 28.5°C | 24.0°C | 19.6°C | 33.0°C | 11.3°C | 211 mm | 76% | 3.6 m/s | 4.1 |
| 1985 | 29.9°C | 24.1°C | 18.3°C | 40.0°C | 2.6°C | 131 mm | 58% | 3.7 m/s | 5.1 |
| 1984 | 30.2°C | 23.6°C | 17.0°C | 39.1°C | 2.7°C | 37 mm | 48% | 3.7 m/s | 4.7 |
| 1983 | 32.0°C | 25.2°C | 18.5°C | 38.1°C | 4.7°C | 36 mm | 52% | 3.6 m/s | — |
| 1982 | 30.4°C | 24.0°C | 17.7°C | 37.6°C | 8.0°C | 51 mm | 55% | 3.2 m/s | — |
| 1981 | 30.4°C | 24.2°C | 18.0°C | 35.2°C | 8.0°C | 35 mm | 59% | 3 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 30.4°C with lows near 18°C (mean 24.2°C), based on 45 years of NASA POWER data.
September averages 88 mm of rainfall in Norman, about average for rainfall. The wettest on record was 212 mm in 1991.
The hottest September reached 44°C in 1998. The coldest dipped to 2.4°C in 1989.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2°C. Daytime highs moved from 30.6°C to 33.1°C and overnight lows from 17.9°C to 19.3°C over the same span.
September is one of the warmer months of the year in Norman and about average for rainfall, so plan for around 30.4°C daytime highs and 18°C at night.
Not quite — September is the 9th coolest month in Norman, averaging 24.2°C.
For September in Norman, pack light, breathable clothing and sun protection, with typical highs of 30.4°C and lows of 18°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 61% — moderately humid.
Average wind speed in September is 2.9 m/s. The windiest September on record averaged 3.7 m/s (1984).
The wettest September on record was 1991 with 212 mm. On average, September sees 88 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Norman behaves each September, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for September specifically, along with year-by-year records and how the month has changed over the decades.
