September is one of the warmer months of the year in Cookeville, with average highs near 28.1°C and lows around 15.3°C (mean 21.7°C). It is one of the drier months, averaging 96 mm of rainfall and 69% relative humidity across the period.
September is one of the warmer months of the year in Cookeville. Across 45 years of records, the warmest September in Cookeville was 2019 — when the month averaged 26.2°C — while the coldest was 1982 at 19.4°C. Typical September days reach 28.1°C with nights near 15.3°C. The long-term trend is warming, about 0.4°C per decade.
September is one of the drier months in Cookeville, averaging 96 mm of rainfall. The wettest September on record was 1989 with 239 mm, while the driest was 2019 at 13 mm.
Relative humidity in Cookeville during September averages 69%. The most humid September was 1989 at 84%, and the least humid was 1999 at 48%.
September receives about 4.6 kWh/m²/day of solar energy in Cookeville. The sunniest September was 2019 at 5.5 kWh/m²/day, and the cloudiest was 2009 at 3.7.
Average wind speed in Cookeville during September is 0.3 m/s. The windiest Septembers were 2011, 2017 and 2024, among others at 0.4 m/s, while the calmest were 2022, 2023 and 2025, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 20.9°C | 21.6°C | 21.8°C | 22.3°C | 21.8°C | +0.9°C |
| Avg High | 27.1°C | 28.4°C | 28.2°C | 28.6°C | 28.2°C | +1.1°C |
| Avg Low | 14.6°C | 14.9°C | 15.4°C | 16.0°C | 15.4°C | +0.8°C |
| Avg Rain | 99 mm | 91 mm | 99 mm | 94 mm | 100 mm | +1 mm |
September temperatures in Cookeville have risen by about 1.5°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 3.2°C (1993) to a record high of 38.4°C (2011).
Rainfall in September is one of the drier months, averaging 96 mm, with a wettest year of 239 mm.
One of the best times to visit Cookeville
September is one of the best times to visit Cookeville. Expect days averaging 28.1°C and nights around 15.3°C (mean 21.7°C) — warmer than Cookeville's yearly average — with higher rainfall (96 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 | 29.4°C | 22.8°C | 16.1°C | 33.6°C | 10.4°C | 113 mm | 67% | 0.3 m/s | 4.9 |
| 2024 | 29.2°C | 22.9°C | 16.6°C | 34.9°C | 9.0°C | 141 mm | 66% | 0.4 m/s | 4.2 |
| 2023 | 29.6°C | 22.6°C | 15.7°C | 33.8°C | 10.9°C | 37 mm | 66% | 0.3 m/s | 4.8 |
| 2022 | 27.5°C | 20.8°C | 14.1°C | 34.8°C | 5.5°C | 98 mm | 70% | 0.3 m/s | 5 |
| 2021 | 26.6°C | 20.9°C | 15.1°C | 31.6°C | 9.1°C | 126 mm | 77% | 0.3 m/s | 4.7 |
| 2020 | 27.0°C | 21.0°C | 15.0°C | 32.5°C | 7.1°C | 86 mm | 76% | 0.3 m/s | 4.4 |
| 2019 🔥 | 33.5°C | 26.2°C | 18.9°C | 37.2°C | 14.4°C | 13 mm | 61% | 0.3 m/s | 5.5 |
| 2018 | 29.4°C | 24.2°C | 19.1°C | 34.4°C | 14.2°C | 200 mm | 79% | 0.3 m/s | 4 |
| 2017 | 26.5°C | 20.3°C | 14.2°C | 31.7°C | 8.8°C | 94 mm | 75% | 0.4 m/s | 4.7 |
| 2016 | 31.4°C | 24.2°C | 17.0°C | 35.0°C | 8.4°C | 53 mm | 63% | 0.3 m/s | 5.3 |
| 2015 | 28.2°C | 21.8°C | 15.5°C | 33.7°C | 8.1°C | 85 mm | 71% | 0.3 m/s | 4.8 |
| 2014 | 28.0°C | 21.9°C | 15.9°C | 32.0°C | 7.3°C | 44 mm | 75% | 0.3 m/s | 4.5 |
| 2013 | 27.4°C | 21.4°C | 15.4°C | 31.6°C | 8.8°C | 72 mm | 76% | 0.3 m/s | 5 |
| 2012 | 26.4°C | 20.4°C | 14.4°C | 33.7°C | 4.1°C | 154 mm | 74% | 0.3 m/s | 4.6 |
| 2011 | 25.0°C | 19.6°C | 14.2°C | 38.4°C | 7.5°C | 179 mm | 75% | 0.4 m/s | 4 |
| 2010 | 29.8°C | 22.6°C | 15.5°C | 35.2°C | 9.2°C | 42 mm | 63% | 0.3 m/s | 5.3 |
| 2009 | 26.1°C | 21.3°C | 16.6°C | 30.4°C | 6.7°C | 197 mm | 82% | 0.3 m/s | 3.7 |
| 2008 | 29.6°C | 22.8°C | 16.0°C | 34.2°C | 10.9°C | 14 mm | 65% | 0.4 m/s | 4.7 |
| 2007 | 30.9°C | 23.8°C | 16.8°C | 36.1°C | 8.6°C | 60 mm | 60% | 0.3 m/s | 5 |
| 2006 | 26.2°C | 19.9°C | 13.6°C | 32.0°C | 6.6°C | 105 mm | 71% | 0.3 m/s | 4.1 |
| 2005 | 30.4°C | 23.2°C | 16.1°C | 34.1°C | 7.1°C | 52 mm | 66% | 0.4 m/s | 5.3 |
| 2004 | 27.1°C | 21.2°C | 15.2°C | 33.5°C | 9.3°C | 129 mm | 77% | 0.3 m/s | 4.5 |
| 2003 | 26.0°C | 20.0°C | 14.0°C | 31.4°C | 4.1°C | 148 mm | 76% | 0.3 m/s | 4.8 |
| 2002 | 30.0°C | 23.6°C | 17.2°C | 35.5°C | 9.7°C | 140 mm | 67% | 0.3 m/s | 4.5 |
| 2001 | 27.2°C | 20.4°C | 13.6°C | 33.7°C | 5.4°C | 75 mm | 66% | 0.4 m/s | 4.9 |
| 2000 | 28.4°C | 21.6°C | 14.7°C | 32.6°C | 5.2°C | 73 mm | 65% | 0.4 m/s | 4.3 |
| 1999 | 29.5°C | 21.6°C | 13.6°C | 36.0°C | 6.5°C | 35 mm | 48% | 0.4 m/s | 5.2 |
| 1998 | 32.4°C | 24.8°C | 17.3°C | 36.9°C | 9.6°C | 25 mm | 57% | 0.4 m/s | 5.3 |
| 1997 | 28.4°C | 21.5°C | 14.6°C | 34.1°C | 8.7°C | 128 mm | 67% | 0.3 m/s | 4.8 |
| 1996 | 26.0°C | 19.9°C | 13.8°C | 30.6°C | 5.4°C | 152 mm | 75% | 0.4 m/s | 4.2 |
| 1995 | 27.7°C | 21.1°C | 14.5°C | 33.0°C | 6.2°C | 100 mm | 68% | 0.3 m/s | 4.3 |
| 1994 | 27.7°C | 20.6°C | 13.5°C | 32.7°C | 6.9°C | 71 mm | 68% | 0.3 m/s | 4.7 |
| 1993 | 28.3°C | 21.2°C | 14.1°C | 35.8°C | 3.2°C | 94 mm | 65% | 0.4 m/s | 4.3 |
| 1992 | 26.0°C | 20.5°C | 15.1°C | 30.4°C | 3.6°C | 131 mm | 80% | 0.3 m/s | 4.2 |
| 1991 | 28.5°C | 22.2°C | 15.9°C | 35.4°C | 3.7°C | 89 mm | 67% | 0.3 m/s | 4.4 |
| 1990 | 29.6°C | 22.9°C | 16.2°C | 37.8°C | 4.7°C | 84 mm | 63% | 0.3 m/s | 4.7 |
| 1989 🌧️ | 25.1°C | 20.0°C | 15.0°C | 30.1°C | 4.8°C | 239 mm | 84% | 0.3 m/s | 4 |
| 1988 | 27.7°C | 21.6°C | 15.5°C | 33.2°C | 7.8°C | 133 mm | 75% | 0.4 m/s | 4 |
| 1987 | 27.5°C | 21.3°C | 15.1°C | 31.6°C | 9.5°C | 98 mm | 66% | 0.4 m/s | 4.3 |
| 1986 | 27.5°C | 22.2°C | 16.8°C | 31.6°C | 11.5°C | 133 mm | 79% | 0.3 m/s | 4.3 |
| 1985 | 27.6°C | 20.7°C | 13.7°C | 33.6°C | 5.1°C | 75 mm | 64% | 0.4 m/s | 5.1 |
| 1984 | 28.0°C | 20.7°C | 13.4°C | 35.1°C | 7.2°C | 19 mm | 59% | 0.4 m/s | 4.5 |
| 1983 | 28.7°C | 21.9°C | 15.1°C | 35.8°C | 3.6°C | 38 mm | 61% | 0.3 m/s | — |
| 1982 ❄️ | 25.0°C | 19.4°C | 13.9°C | 29.3°C | 6.3°C | 84 mm | 79% | 0.3 m/s | — |
| 1981 | 26.9°C | 19.9°C | 12.9°C | 31.6°C | 5.0°C | 77 mm | 67% | 0.4 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 28.1°C with lows near 15.3°C (mean 21.7°C), based on 45 years of NASA POWER data.
September averages 96 mm of rainfall in Cookeville, one of the drier months. The wettest on record was 239 mm in 1989.
The hottest September reached 38.4°C in 2011. The coldest dipped to 3.2°C in 1993.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.5°C. Daytime highs moved from 27.2°C to 28.5°C and overnight lows from 13.8°C to 15.5°C over the same span.
September is one of the warmer months of the year in Cookeville and one of the drier months, so plan for around 28.1°C daytime highs and 15.3°C at night.
Not quite — September is the 9th coolest month in Cookeville, averaging 21.7°C.
For September in Cookeville, pack light layers you can adjust through the day, with typical highs of 28.1°C and lows of 15.3°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 69% — moderately humid.
Average wind speed in September is 0.3 m/s. The windiest September on record averaged 0.4 m/s (1981).
The wettest September on record was 1989 with 239 mm. On average, September sees 96 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 Cookeville 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.
