September is one of the warmer months of the year in Apache Junction, with average highs near 34°C and lows around 19.8°C (mean 26.9°C). It is about average for rainfall, averaging 33 mm of rainfall and 38% relative humidity across the period.
September is one of the warmer months of the year in Apache Junction. Across 45 years of records, the warmest September in Apache Junction was 2024 — when the month averaged 29.8°C — while the coldest was 1985 at 23.2°C. Typical September days reach 34°C with nights near 19.8°C. The long-term trend is warming, about 0.6°C per decade.
September is about average for rainfall in Apache Junction, averaging 33 mm of rainfall. The wettest September on record was 1983 with 125 mm, while the driest was 2020 at 2 mm.
Relative humidity in Apache Junction during September averages 38%. The most humid September was 1983 at 52%, and the least humid was 2020 at 24%.
September receives about 6 kWh/m²/day of solar energy in Apache Junction. The sunniest Septembers were 1993 and 2001 at 6.5 kWh/m²/day, and the cloudiest were 1984, 2015 and 2025 at 5.6.
Average wind speed in Apache Junction during September is 2.1 m/s. The windiest September was 1989 at 2.5 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 | 25.7°C | 26.5°C | 27.0°C | 27.4°C | 28.4°C | +2.7°C |
| Avg High | 32.9°C | 33.5°C | 34.3°C | 34.3°C | 35.5°C | +2.6°C |
| Avg Low | 18.4°C | 19.5°C | 19.6°C | 20.5°C | 21.3°C | +2.9°C |
| Avg Rain | 47 mm | 36 mm | 24 mm | 31 mm | 25 mm | -22 mm |
September temperatures in Apache Junction have risen by about 2.3°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 8.7°C (1986) to a record high of 42.6°C (2020).
Rainfall in September is about average for rainfall, averaging 33 mm, with a wettest year of 125 mm.
One of the best times to visit Apache Junction
September is one of the best times to visit Apache Junction. Expect days averaging 34°C and nights around 19.8°C (mean 26.9°C) — warmer than Apache Junction's yearly average — with moderate rainfall (33 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 | 34.4°C | 27.9°C | 21.3°C | 38.0°C | 16.6°C | 60 mm | 43% | 1.9 m/s | 5.6 |
| 2024 🔥 | 37.3°C | 29.8°C | 22.2°C | 42.5°C | 15.5°C | 5 mm | 24% | 2.3 m/s | 6.4 |
| 2023 | 35.4°C | 28.2°C | 21.0°C | 41.8°C | 17.3°C | 25 mm | 30% | 2 m/s | 6.1 |
| 2022 | 35.1°C | 28.3°C | 21.5°C | 39.1°C | 18.1°C | 27 mm | 44% | 1.9 m/s | 5.9 |
| 2021 | 34.0°C | 27.5°C | 21.0°C | 38.9°C | 15.4°C | 32 mm | 45% | 1.7 m/s | 5.8 |
| 2020 | 36.6°C | 28.9°C | 21.1°C | 42.6°C | 14.0°C | 2 mm | 24% | 2.1 m/s | 6.2 |
| 2019 | 33.9°C | 27.5°C | 21.0°C | 41.0°C | 15.7°C | 50 mm | 41% | 2 m/s | 5.8 |
| 2018 | 36.1°C | 29.3°C | 22.5°C | 39.9°C | 19.4°C | 15 mm | 31% | 1.8 m/s | 6.3 |
| 2017 | 34.3°C | 26.9°C | 19.5°C | 40.5°C | 11.3°C | 5 mm | 30% | 2.1 m/s | 6.4 |
| 2016 | 33.2°C | 26.3°C | 19.5°C | 38.0°C | 11.5°C | 15 mm | 37% | 2.2 m/s | 5.7 |
| 2015 | 34.3°C | 27.7°C | 21.1°C | 38.2°C | 18.1°C | 19 mm | 44% | 1.8 m/s | 5.6 |
| 2014 | 33.2°C | 27.0°C | 20.8°C | 38.1°C | 12.9°C | 83 mm | 50% | 1.9 m/s | 5.9 |
| 2013 | 33.5°C | 26.5°C | 19.6°C | 39.4°C | 10.7°C | 32 mm | 41% | 2.1 m/s | 6 |
| 2012 | 33.3°C | 26.5°C | 19.7°C | 37.7°C | 14.6°C | 26 mm | 42% | 1.9 m/s | 5.8 |
| 2011 | 35.6°C | 28.1°C | 20.6°C | 40.3°C | 16.0°C | 26 mm | 32% | 2 m/s | 6.1 |
| 2010 | 35.9°C | 28.1°C | 20.3°C | 39.6°C | 15.2°C | 34 mm | 33% | 2 m/s | 6.4 |
| 2009 | 34.1°C | 26.9°C | 19.8°C | 38.3°C | 15.2°C | 38 mm | 36% | 2 m/s | 6.2 |
| 2008 | 33.8°C | 26.6°C | 19.5°C | 38.0°C | 15.5°C | 17 mm | 41% | 2.1 m/s | 6.4 |
| 2007 | 33.8°C | 27.0°C | 20.2°C | 37.9°C | 13.0°C | 23 mm | 38% | 2 m/s | 6.1 |
| 2006 | 31.5°C | 24.2°C | 17.0°C | 37.0°C | 9.8°C | 31 mm | 44% | 2.2 m/s | 6.1 |
| 2005 | 34.5°C | 27.2°C | 19.9°C | 37.8°C | 13.9°C | 15 mm | 32% | 2.1 m/s | 6.1 |
| 2004 | 33.7°C | 26.0°C | 18.4°C | 39.0°C | 11.1°C | 44 mm | 34% | 2.3 m/s | 6.3 |
| 2003 | 35.2°C | 27.7°C | 20.1°C | 39.7°C | 15.5°C | 33 mm | 36% | 2.1 m/s | 6 |
| 2002 | 34.4°C | 27.1°C | 19.8°C | 39.9°C | 14.7°C | 32 mm | 36% | 2.2 m/s | 6 |
| 2001 | 36.2°C | 28.5°C | 20.7°C | 39.2°C | 17.3°C | 7 mm | 29% | 2.4 m/s | 6.5 |
| 2000 | 36.1°C | 28.4°C | 20.7°C | 41.2°C | 13.4°C | 3 mm | 28% | 2.3 m/s | 6.2 |
| 1999 | 34.1°C | 26.9°C | 19.6°C | 38.1°C | 15.0°C | 40 mm | 43% | 2.2 m/s | 6 |
| 1998 | 34.7°C | 27.5°C | 20.2°C | 38.8°C | 15.3°C | 29 mm | 34% | 2.3 m/s | 5.9 |
| 1997 | 35.6°C | 28.7°C | 21.7°C | 39.0°C | 16.3°C | 22 mm | 40% | 2.1 m/s | 5.8 |
| 1996 | 30.9°C | 24.4°C | 17.9°C | 35.9°C | 12.1°C | 65 mm | 49% | 1.9 m/s | 5.8 |
| 1995 | 34.1°C | 27.2°C | 20.3°C | 39.6°C | 11.1°C | 42 mm | 40% | 2 m/s | 6.2 |
| 1994 | 33.5°C | 26.9°C | 20.2°C | 37.3°C | 14.0°C | 42 mm | 41% | 1.8 m/s | 5.8 |
| 1993 | 33.6°C | 25.6°C | 17.6°C | 37.4°C | 11.6°C | 16 mm | 38% | 2.1 m/s | 6.5 |
| 1992 | 33.6°C | 26.3°C | 19.0°C | 36.4°C | 16.2°C | 15 mm | 40% | 2 m/s | 6.3 |
| 1991 | 32.6°C | 25.7°C | 18.8°C | 36.4°C | 15.0°C | 33 mm | 43% | 2.1 m/s | 5.9 |
| 1990 | 32.2°C | 25.8°C | 19.3°C | 38.6°C | 14.1°C | 52 mm | 52% | 1.8 m/s | 5.8 |
| 1989 | 34.8°C | 27.0°C | 19.2°C | 38.0°C | 13.1°C | 9 mm | 27% | 2.5 m/s | 6.3 |
| 1988 | 32.8°C | 24.8°C | 16.8°C | 36.5°C | 10.7°C | 10 mm | 37% | 2.3 m/s | 6.2 |
| 1987 | 32.9°C | 25.5°C | 18.0°C | 37.4°C | 12.9°C | 20 mm | 34% | 2.2 m/s | 5.8 |
| 1986 | 31.2°C | 23.6°C | 16.1°C | 37.8°C | 8.7°C | 28 mm | 41% | 2.3 m/s | 5.8 |
| 1985 ❄️ | 30.3°C | 23.2°C | 16.2°C | 35.2°C | 11.6°C | 86 mm | 44% | 2.2 m/s | 5.8 |
| 1984 | 33.2°C | 26.4°C | 19.6°C | 38.1°C | 14.0°C | 75 mm | 49% | 2.3 m/s | 5.6 |
| 1983 🌧️ | 33.6°C | 27.3°C | 21.0°C | 39.4°C | 15.1°C | 125 mm | 52% | 1.9 m/s | — |
| 1982 | 32.8°C | 25.8°C | 18.9°C | 40.0°C | 10.6°C | 50 mm | 46% | 2.3 m/s | — |
| 1981 | 34.6°C | 27.3°C | 20.0°C | 37.2°C | 15.1°C | 22 mm | 35% | 2.1 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 34°C with lows near 19.8°C (mean 26.9°C), based on 45 years of NASA POWER data.
September averages 33 mm of rainfall in Apache Junction, about average for rainfall. The wettest on record was 125 mm in 1983.
The hottest September reached 42.6°C in 2020. The coldest dipped to 8.7°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.3°C. Daytime highs moved from 32.9°C to 35.2°C and overnight lows from 19.1°C to 21.4°C over the same span.
September is one of the warmer months of the year in Apache Junction and about average for rainfall, so plan for around 34°C daytime highs and 19.8°C at night.
Not quite — September is the 9th coolest month in Apache Junction, averaging 26.9°C.
For September in Apache Junction, pack light, breathable clothing and sun protection, with typical highs of 34°C and lows of 19.8°C.
Relative humidity in September averages 38% — relatively dry.
Average wind speed in September is 2.1 m/s. The windiest September on record averaged 2.5 m/s (1989).
The wettest September on record was 1983 with 125 mm. On average, September sees 33 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 Apache Junction 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.
