Climate averages 1991–2020
Tucson weather
in September.
A very hot, fairly dry month: the 4th warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a very hot month in Tucson: daytime highs average 34.1°C and nights cool to about 21.3°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 25 mm of rain on roughly 4 days, which makes September a fairly dry month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 24 min on an average September day.
The nearest other city in this atlas is Nogales (102 km away). In September its highs average 30.2°C, 4.0°C cooler than Tucson, with 49 mm of rain.
Among the 498 cities listed in the United States, Tucson ranks joint 14th of 498 for the warmest September highs and joint 132nd of 498 for the driest September (rainfall, lowest first). The mean September high of those 498 cities is 26.9°C; Tucson is 7.2°C warmer than that mean.
From September to October, average highs fall by 5.0°C to 29.2°C, and monthly rainfall falls from 25 mm to 14 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Tucson climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 17.6°C4.0°C | 4.0°C | 29 | 4.0 | 10.310 h |
| February | 19.3°C5.4°C | 5.4°C | 28 | 3.8 | 11.011 h |
| March | 23.3°C8.5°C | 8.5°C | 17 | 3.0 | 12.012 h |
| April | 27.6°C12.3°C | 12.3°C | 6.0 | 1.4 | 12.913 h |
| May | 32.4°C17.2°C | 17.2°C | 2.7 | 0.8 | 13.814 h |
| June | 37.5°C22.6°C | 22.6°C | 4.6 | 1.2 | 14.214 h |
| July | 36.8°C25.1°C | 25.1°C | 33 | 7.8 | 14.014 h |
| August | 36.0°C24.4°C | 24.4°C | 33 | 7.5 | 13.313 h |
| September, selected | 34.1°C21.3°C | 21.3°C | 25 | 3.7 | 12.412 h |
| October | 29.2°C14.9°C | 14.9°C | 14 | 2.3 | 11.411 h |
| November | 22.6°C8.5°C | 8.5°C | 17 | 2.5 | 10.511 h |
| December | 17.1°C3.8°C | 3.8°C | 31 | 4.3 | 10.110 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Nogales in SeptemberMexico · 102 kmHigh 30.2°C · Low 17.3°C · 49 mm rain
- San Tan Valley in SeptemberUnited States · 122 kmHigh 35.9°C · Low 22.7°C · 26 mm rain
- Chandler in SeptemberUnited States · 148 kmHigh 37.0°C · Low 23.1°C · 25 mm rain
- Mesa in SeptemberUnited States · 158 kmHigh 36.6°C · Low 22.8°C · 26 mm rain
- Tempe in SeptemberUnited States · 161 kmHigh 36.8°C · Low 23.2°C · 24 mm rain
- Agua Prieta in SeptemberMexico · 165 kmHigh 30.8°C · Low 18.3°C · 30 mm rain
- Scottsdale in SeptemberUnited States · 170 kmHigh 36.5°C · Low 23.1°C · 24 mm rain
- Phoenix in SeptemberUnited States · 173 kmHigh 36.9°C · Low 23.4°C · 24 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Tucson) is explained once on the Tucson year overview and on the Sources, method and limits page.