July is one of the warmer months of the year in Decatur, with average highs near 32.2°C and lows around 21.3°C (mean 26.8°C). It is about average for rainfall, averaging 117 mm of rainfall and 72% relative humidity across the period.
July is one of the warmer months of the year in Decatur. Across 45 years of records, the warmest July in Decatur was 1993 — when the month averaged 29°C — while the coldest were 1994 and 2013 at 24.4°C. Typical July days reach 32.2°C with nights near 21.3°C. The long-term July temperature trend is broadly flat.
July is about average for rainfall in Decatur, averaging 117 mm of rainfall. The wettest July on record was 2013 with 235 mm, while the driest was 2000 at 44 mm.
Relative humidity in Decatur during July averages 72%. The most humid July was 1989 at 85%, and the least humid was 2000 at 56%.
July receives about 6 kWh/m²/day of solar energy in Decatur. The sunniest July was 2025 at 6.7 kWh/m²/day, and the cloudiest were 1988 and 2007 at 5.4.
Average wind speed in Decatur during July is 0.8 m/s. The windiest Julys were 2000 and 2009 at 1 m/s, while the calmest were 2018, 2020 and 2025, among others at 0.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 26.5°C | 26.7°C | 26.6°C | 26.9°C | 27.3°C | +0.8°C |
| Avg High | 32.1°C | 32.0°C | 32.3°C | 32.1°C | 32.6°C | +0.5°C |
| Avg Low | 21.0°C | 21.4°C | 20.9°C | 21.6°C | 21.9°C | +0.9°C |
| Avg Rain | 124 mm | 104 mm | 109 mm | 126 mm | 126 mm | +2 mm |
July temperatures in Decatur have risen by about 1°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 13.7°C (2009) to a record high of 40.6°C (1986).
Rainfall in July is about average for rainfall, averaging 117 mm, with a wettest year of 235 mm.
A good time to visit Decatur
July is a good time to visit Decatur, with days averaging 32.2°C and nights around 21.3°C (mean 26.8°C, warmer than Decatur's yearly average) and higher rainfall. September and May are marginally more temperate, but July still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 32.8°C | 27.6°C | 22.5°C | 36.8°C | 19.2°C | 70 mm | 76% | 0.7 m/s | 6.7 |
| 2024 | 33.8°C | 28.0°C | 22.1°C | 38.8°C | 19.5°C | 145 mm | 68% | 0.8 m/s | 5.5 |
| 2023 | 32.4°C | 27.1°C | 21.7°C | 37.4°C | 18.2°C | 136 mm | 73% | 0.8 m/s | 6.1 |
| 2022 | 35.0°C | 28.8°C | 22.7°C | 37.3°C | 20.3°C | 108 mm | 68% | 0.8 m/s | 6.2 |
| 2021 | 29.5°C | 25.1°C | 20.7°C | 34.8°C | 15.1°C | 183 mm | 82% | 0.8 m/s | 5.7 |
| 2020 | 31.9°C | 26.9°C | 21.9°C | 34.3°C | 19.8°C | 113 mm | 76% | 0.7 m/s | 6.4 |
| 2019 | 31.8°C | 26.8°C | 21.7°C | 35.7°C | 16.2°C | 138 mm | 74% | 0.8 m/s | 6.1 |
| 2018 | 31.7°C | 26.7°C | 21.7°C | 34.2°C | 18.2°C | 66 mm | 75% | 0.7 m/s | 6.3 |
| 2017 | 31.8°C | 26.7°C | 21.6°C | 35.9°C | 17.7°C | 136 mm | 76% | 0.7 m/s | 6.5 |
| 2016 | 33.8°C | 28.2°C | 22.6°C | 37.6°C | 19.4°C | 118 mm | 69% | 0.8 m/s | 6.2 |
| 2015 | 31.6°C | 26.9°C | 22.1°C | 35.5°C | 19.0°C | 124 mm | 78% | 0.9 m/s | 6.2 |
| 2014 | 30.2°C | 24.6°C | 18.9°C | 33.9°C | 13.7°C | 84 mm | 72% | 0.9 m/s | 6.4 |
| 2013 🌧️ | 28.7°C | 24.4°C | 20.1°C | 32.6°C | 16.2°C | 235 mm | 83% | 0.8 m/s | 5.5 |
| 2012 | 33.7°C | 28.0°C | 22.3°C | 40.0°C | 19.3°C | 171 mm | 69% | 0.8 m/s | 6.1 |
| 2011 | 33.4°C | 27.9°C | 22.3°C | 37.1°C | 18.1°C | 97 mm | 72% | 0.7 m/s | 6.1 |
| 2010 | 34.5°C | 28.7°C | 22.8°C | 38.5°C | 17.7°C | 89 mm | 68% | 0.8 m/s | 6.6 |
| 2009 | 30.1°C | 24.8°C | 19.4°C | 33.1°C | 13.7°C | 143 mm | 75% | 1 m/s | 6 |
| 2008 | 33.8°C | 27.3°C | 20.8°C | 37.6°C | 15.6°C | 92 mm | 63% | 0.8 m/s | 6.3 |
| 2007 | 31.7°C | 26.1°C | 20.6°C | 34.8°C | 14.8°C | 116 mm | 70% | 0.8 m/s | 5.4 |
| 2006 | 34.8°C | 28.3°C | 21.8°C | 38.8°C | 16.1°C | 72 mm | 61% | 0.8 m/s | 6 |
| 2005 | 31.8°C | 26.9°C | 22.0°C | 37.0°C | 19.7°C | 161 mm | 76% | 0.9 m/s | 5.5 |
| 2004 | 30.5°C | 25.6°C | 20.7°C | 34.3°C | 15.3°C | 119 mm | 78% | 0.8 m/s | 6.1 |
| 2003 | 29.2°C | 24.8°C | 20.4°C | 31.6°C | 16.1°C | 129 mm | 81% | 0.9 m/s | 5.9 |
| 2002 | 33.4°C | 27.5°C | 21.7°C | 36.9°C | 18.6°C | 113 mm | 69% | 0.7 m/s | 6 |
| 2001 | 32.0°C | 26.2°C | 20.4°C | 34.5°C | 14.7°C | 102 mm | 70% | 0.8 m/s | 6.1 |
| 2000 | 35.3°C | 28.1°C | 20.9°C | 38.9°C | 16.4°C | 44 mm | 56% | 1 m/s | 6.6 |
| 1999 | 32.9°C | 27.2°C | 21.6°C | 39.3°C | 18.5°C | 87 mm | 71% | 0.7 m/s | 6.3 |
| 1998 | 32.8°C | 27.6°C | 22.3°C | 38.2°C | 19.9°C | 127 mm | 74% | 0.9 m/s | 5.5 |
| 1997 | 30.8°C | 25.8°C | 20.8°C | 35.6°C | 15.8°C | 60 mm | 78% | 0.8 m/s | 6.5 |
| 1996 | 32.0°C | 26.3°C | 20.7°C | 36.8°C | 16.1°C | 167 mm | 70% | 0.9 m/s | 5.6 |
| 1995 | 34.3°C | 28.0°C | 21.8°C | 38.4°C | 18.5°C | 85 mm | 64% | 0.9 m/s | 6.3 |
| 1994 ❄️ | 28.2°C | 24.4°C | 20.5°C | 31.1°C | 15.6°C | 158 mm | 84% | 0.8 m/s | 5.5 |
| 1993 🔥 | 35.3°C | 29.0°C | 22.7°C | 38.1°C | 18.2°C | 52 mm | 64% | 0.7 m/s | 6.6 |
| 1992 | 30.9°C | 26.2°C | 21.4°C | 35.4°C | 18.6°C | 132 mm | 78% | 0.9 m/s | 5.6 |
| 1991 | 30.3°C | 25.9°C | 21.5°C | 32.8°C | 18.6°C | 81 mm | 81% | 0.8 m/s | 6.3 |
| 1990 | 32.0°C | 26.1°C | 20.2°C | 35.9°C | 15.1°C | 96 mm | 69% | 0.8 m/s | 6 |
| 1989 | 28.5°C | 24.6°C | 20.8°C | 32.0°C | 18.2°C | 194 mm | 85% | 0.8 m/s | 5.6 |
| 1988 | 33.1°C | 27.1°C | 21.1°C | 38.9°C | 17.3°C | 134 mm | 65% | 0.8 m/s | 5.4 |
| 1987 | 32.8°C | 26.9°C | 21.0°C | 38.5°C | 15.7°C | 85 mm | 67% | 0.8 m/s | 6.2 |
| 1986 | 35.4°C | 28.8°C | 22.2°C | 40.6°C | 16.5°C | 76 mm | 60% | 0.9 m/s | 6.4 |
| 1985 | 31.4°C | 25.8°C | 20.3°C | 35.3°C | 16.2°C | 215 mm | 71% | 0.7 m/s | 5.6 |
| 1984 | 31.0°C | 25.4°C | 19.8°C | 34.8°C | 15.6°C | 149 mm | 72% | 0.9 m/s | 5.6 |
| 1983 | 31.5°C | 26.3°C | 21.0°C | 34.6°C | 14.0°C | 52 mm | 73% | 0.8 m/s | — |
| 1982 | 30.7°C | 26.0°C | 21.3°C | 33.4°C | 18.5°C | 122 mm | 78% | 0.7 m/s | — |
| 1981 | 34.2°C | 28.0°C | 21.7°C | 37.2°C | 17.0°C | 91 mm | 65% | 0.9 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 32.2°C with lows near 21.3°C (mean 26.8°C), based on 45 years of NASA POWER data.
July averages 117 mm of rainfall in Decatur, about average for rainfall. The wettest on record was 235 mm in 2013.
The hottest July reached 40.6°C in 1986. The coldest dipped to 13.7°C in 2009.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 1°C. Daytime highs moved from 31.8°C to 32.7°C and overnight lows from 20.8°C to 21.9°C over the same span.
July is one of the warmer months of the year in Decatur and about average for rainfall, so plan for around 32.2°C daytime highs and 21.3°C at night.
Not quite — July is the 12th coolest month in Decatur, averaging 26.8°C.
For July in Decatur, pack light, breathable clothing and sun protection, with typical highs of 32.2°C and lows of 21.3°C. Bring an umbrella or light rain jacket too.
Relative humidity in July averages 72% — moderately humid.
Average wind speed in July is 0.8 m/s. The windiest July on record averaged 1 m/s (2000).
The wettest July on record was 2013 with 235 mm. On average, July sees 117 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 Decatur behaves each July, 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 July specifically, along with year-by-year records and how the month has changed over the decades.
