September is one of the warmer months of the year in Tucson, with average highs near 33.6°C and lows around 19.7°C (mean 26.7°C). It is about average for rainfall, averaging 40 mm of rainfall and 44% relative humidity across the period.
September is one of the warmer months of the year in Tucson. Across 45 years of records, the warmest September in Tucson was 2024 — when the month averaged 28.9°C — while the coldest was 1985 at 23.7°C. Typical September days reach 33.6°C with nights near 19.7°C. The long-term trend is warming, about 0.5°C per decade.
September is about average for rainfall in Tucson, averaging 40 mm of rainfall. The wettest September on record was 1983 with 174 mm, while the driest was 2020 at 2 mm.
Relative humidity in Tucson during September averages 44%. The most humid September was 1983 at 61%, and the least humid was 2023 at 29%.
September receives about 5.9 kWh/m²/day of solar energy in Tucson. The sunniest September was 2024 at 6.5 kWh/m²/day, and the cloudiest was 2015 at 5.3.
Average wind speed in Tucson during September is 2.2 m/s. The windiest September was 2024 at 2.7 m/s, while the calmest was 2021 at 1.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 25.6°C | 26.5°C | 26.9°C | 26.8°C | 28.1°C | +2.5°C |
| Avg High | 32.6°C | 33.4°C | 34.0°C | 33.5°C | 35.2°C | +2.6°C |
| Avg Low | 18.5°C | 19.5°C | 19.9°C | 20.1°C | 21.0°C | +2.5°C |
| Avg Rain | 54 mm | 36 mm | 30 mm | 51 mm | 21 mm | -33 mm |
September temperatures in Tucson have risen by about 2.2°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 9.3°C (1986) to a record high of 41.6°C (2020).
Rainfall in September is about average for rainfall, averaging 40 mm, with a wettest year of 174 mm.
One of the best times to visit Tucson
September is one of the best times to visit Tucson. Expect days averaging 33.6°C and nights around 19.7°C (mean 26.7°C) — warmer than Tucson's yearly average — with moderate rainfall (40 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 | 34.3°C | 27.7°C | 21.2°C | 38.7°C | 16.0°C | 32 mm | 48% | 2 m/s | 5.5 |
| 2024 🔥 | 36.8°C | 28.9°C | 21.1°C | 41.3°C | 14.7°C | 6 mm | 30% | 2.7 m/s | 6.5 |
| 2023 | 36.4°C | 28.8°C | 21.2°C | 41.5°C | 17.4°C | 11 mm | 29% | 2.3 m/s | 6 |
| 2022 | 33.8°C | 27.3°C | 20.8°C | 37.3°C | 17.1°C | 44 mm | 51% | 2.2 m/s | 5.9 |
| 2021 | 33.6°C | 27.1°C | 20.5°C | 37.9°C | 16.0°C | 30 mm | 49% | 1.7 m/s | 5.9 |
| 2020 | 36.4°C | 28.8°C | 21.3°C | 41.6°C | 14.8°C | 2 mm | 29% | 2.4 m/s | 6.3 |
| 2019 | 33.4°C | 26.8°C | 20.3°C | 39.7°C | 15.9°C | 65 mm | 50% | 2.2 m/s | 5.6 |
| 2018 | 34.8°C | 28.1°C | 21.4°C | 39.1°C | 18.1°C | 49 mm | 43% | 1.9 m/s | 6.1 |
| 2017 | 33.6°C | 26.2°C | 18.9°C | 38.9°C | 12.6°C | 8 mm | 37% | 2.4 m/s | 6.2 |
| 2016 | 32.1°C | 25.6°C | 19.1°C | 37.0°C | 14.6°C | 54 mm | 46% | 2.3 m/s | 5.5 |
| 2015 | 33.2°C | 27.1°C | 21.0°C | 37.6°C | 18.1°C | 66 mm | 53% | 1.9 m/s | 5.3 |
| 2014 | 32.5°C | 26.4°C | 20.3°C | 38.3°C | 14.2°C | 101 mm | 55% | 2 m/s | 5.4 |
| 2013 | 33.6°C | 26.7°C | 19.7°C | 38.6°C | 11.7°C | 39 mm | 44% | 2 m/s | 5.8 |
| 2012 | 32.0°C | 25.9°C | 19.8°C | 37.3°C | 15.4°C | 54 mm | 50% | 2 m/s | 5.6 |
| 2011 | 34.9°C | 27.8°C | 20.7°C | 39.4°C | 17.2°C | 56 mm | 39% | 1.9 m/s | 5.8 |
| 2010 | 35.2°C | 27.7°C | 20.1°C | 38.6°C | 14.2°C | 20 mm | 40% | 2.1 m/s | 6.2 |
| 2009 | 34.1°C | 27.1°C | 20.2°C | 38.0°C | 16.0°C | 31 mm | 38% | 1.9 m/s | 6 |
| 2008 | 33.4°C | 26.6°C | 19.9°C | 37.5°C | 16.7°C | 32 mm | 45% | 2.2 m/s | 6.2 |
| 2007 | 33.2°C | 26.3°C | 19.3°C | 37.2°C | 13.8°C | 36 mm | 46% | 2.2 m/s | 6 |
| 2006 | 31.0°C | 24.5°C | 18.0°C | 36.3°C | 13.8°C | 54 mm | 51% | 2 m/s | 5.7 |
| 2005 | 33.9°C | 26.9°C | 19.9°C | 38.3°C | 14.1°C | 20 mm | 40% | 2 m/s | 5.8 |
| 2004 | 33.7°C | 26.3°C | 19.0°C | 39.1°C | 12.3°C | 28 mm | 38% | 2.5 m/s | 6.2 |
| 2003 | 35.1°C | 27.9°C | 20.7°C | 38.3°C | 15.9°C | 40 mm | 40% | 2.1 m/s | 6 |
| 2002 | 34.4°C | 27.4°C | 20.4°C | 39.2°C | 14.6°C | 36 mm | 40% | 2.4 m/s | 5.9 |
| 2001 | 35.5°C | 28.2°C | 20.9°C | 39.4°C | 17.2°C | 17 mm | 34% | 2.4 m/s | 6.3 |
| 2000 | 35.8°C | 28.2°C | 20.5°C | 39.7°C | 15.4°C | 11 mm | 36% | 2.1 m/s | 6.2 |
| 1999 | 34.1°C | 27.1°C | 20.1°C | 37.9°C | 16.5°C | 31 mm | 45% | 2 m/s | 6 |
| 1998 | 34.5°C | 27.0°C | 19.6°C | 37.4°C | 14.0°C | 32 mm | 42% | 2.2 m/s | 5.9 |
| 1997 | 34.8°C | 28.0°C | 21.2°C | 38.0°C | 16.3°C | 41 mm | 47% | 1.8 m/s | 5.6 |
| 1996 | 31.6°C | 24.8°C | 17.9°C | 35.1°C | 13.2°C | 59 mm | 50% | 1.9 m/s | 5.6 |
| 1995 | 33.7°C | 27.0°C | 20.4°C | 39.9°C | 14.0°C | 36 mm | 45% | 2.1 m/s | 6.1 |
| 1994 | 33.4°C | 27.0°C | 20.6°C | 37.5°C | 16.7°C | 44 mm | 46% | 1.8 m/s | 5.6 |
| 1993 | 33.3°C | 25.6°C | 17.9°C | 37.1°C | 11.7°C | 17 mm | 42% | 2.3 m/s | 6.4 |
| 1992 | 34.2°C | 26.7°C | 19.2°C | 37.5°C | 16.3°C | 20 mm | 41% | 2.2 m/s | 6.3 |
| 1991 | 32.3°C | 25.5°C | 18.6°C | 37.3°C | 14.6°C | 27 mm | 46% | 2.1 m/s | 5.6 |
| 1990 | 32.1°C | 25.8°C | 19.4°C | 37.7°C | 15.3°C | 53 mm | 54% | 1.9 m/s | 5.5 |
| 1989 | 34.6°C | 26.9°C | 19.1°C | 38.3°C | 13.0°C | 11 mm | 33% | 2.6 m/s | 6.2 |
| 1988 | 32.6°C | 25.0°C | 17.4°C | 37.0°C | 11.9°C | 10 mm | 40% | 2.5 m/s | 5.9 |
| 1987 | 31.6°C | 24.8°C | 18.0°C | 36.6°C | 12.4°C | 45 mm | 43% | 2.1 m/s | 5.6 |
| 1986 | 32.0°C | 24.5°C | 17.0°C | 37.9°C | 9.3°C | 20 mm | 42% | 2.5 m/s | 6.1 |
| 1985 ❄️ | 30.8°C | 23.7°C | 16.6°C | 35.8°C | 11.0°C | 55 mm | 45% | 2.6 m/s | 5.8 |
| 1984 | 32.5°C | 25.7°C | 18.8°C | 37.1°C | 14.5°C | 58 mm | 55% | 2.6 m/s | 5.7 |
| 1983 🌧️ | 32.4°C | 26.7°C | 21.1°C | 38.7°C | 16.0°C | 174 mm | 61% | 1.9 m/s | — |
| 1982 | 33.1°C | 25.8°C | 18.5°C | 39.8°C | 11.5°C | 55 mm | 48% | 2.4 m/s | — |
| 1981 | 33.9°C | 26.9°C | 19.9°C | 36.5°C | 15.9°C | 54 mm | 43% | 1.9 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 33.6°C with lows near 19.7°C (mean 26.7°C), based on 45 years of NASA POWER data.
September averages 40 mm of rainfall in Tucson, about average for rainfall. The wettest on record was 174 mm in 1983.
The hottest September reached 41.6°C in 2020. The coldest dipped to 9.3°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.2°C. Daytime highs moved from 32.5°C to 35°C and overnight lows from 19°C to 21°C over the same span.
September is one of the warmer months of the year in Tucson and about average for rainfall, so plan for around 33.6°C daytime highs and 19.7°C at night.
Not quite — September is the 9th coolest month in Tucson, averaging 26.7°C.
For September in Tucson, pack light, breathable clothing and sun protection, with typical highs of 33.6°C and lows of 19.7°C.
Relative humidity in September averages 44% — relatively dry.
Average wind speed in September is 2.2 m/s. The windiest September on record averaged 2.7 m/s (2024).
The wettest September on record was 1983 with 174 mm. On average, September sees 40 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 Tucson 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.
