August is one of the warmer months of the year in Grand Junction, with average highs near 30.1°C and lows around 14.6°C (mean 22.4°C). It is about average for rainfall, averaging 36 mm of rainfall and 41% relative humidity across the period.
August is one of the warmer months of the year in Grand Junction. Across 45 years of records, the warmest August in Grand Junction was 2020 — when the month averaged 25.4°C — while the coldest were 1987 and 1999 at 20.3°C. Typical August days reach 30.1°C with nights near 14.6°C. The long-term trend is warming, about 0.4°C per decade.
August is about average for rainfall in Grand Junction, averaging 36 mm of rainfall. The wettest August on record was 2014 with 75 mm, while the driest was 1985 at 5 mm.
Relative humidity in Grand Junction during August averages 41%. The most humid August was 1999 at 54%, and the least humid was 2020 at 23%.
August receives about 6.5 kWh/m²/day of solar energy in Grand Junction. The sunniest August was 1985 at 7 kWh/m²/day, and the cloudiest were 1999 and 2013 at 5.9.
Average wind speed in Grand Junction during August is 2 m/s. The windiest August was 2002 at 2.4 m/s, while the calmest were 1983 and 2022 at 1.6 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 21.7°C | 22.0°C | 22.3°C | 22.5°C | 23.7°C | +2°C |
| Avg High | 29.4°C | 29.7°C | 30.0°C | 30.3°C | 31.5°C | +2.1°C |
| Avg Low | 14.1°C | 14.3°C | 14.7°C | 14.8°C | 15.9°C | +1.8°C |
| Avg Rain | 37 mm | 37 mm | 35 mm | 38 mm | 37 mm | +0 mm |
August temperatures in Grand Junction have risen by about 1.3°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 4.9°C (1992) to a record high of 38°C (2000).
Rainfall in August is about average for rainfall, averaging 36 mm, with a wettest year of 75 mm.
One of the best times to visit Grand Junction
August is one of the best times to visit Grand Junction. Expect days averaging 30.1°C and nights around 14.6°C (mean 22.4°C) — warmer than Grand Junction's yearly average — with moderate rainfall (36 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 | 31.8°C | 23.9°C | 16.0°C | 37.0°C | 10.9°C | 19 mm | 31% | 2.1 m/s | 6.5 |
| 2024 | 30.7°C | 23.3°C | 15.9°C | 37.0°C | 10.9°C | 72 mm | 47% | 2.1 m/s | 6.3 |
| 2023 | 31.4°C | 23.9°C | 16.4°C | 34.7°C | 13.3°C | 38 mm | 41% | 2.1 m/s | 6.6 |
| 2022 | 30.0°C | 23.0°C | 16.0°C | 35.1°C | 11.7°C | 44 mm | 49% | 1.6 m/s | 6.3 |
| 2021 | 30.8°C | 22.6°C | 14.3°C | 35.4°C | 6.8°C | 41 mm | 40% | 2 m/s | 6.7 |
| 2020 🔥 | 34.1°C | 25.4°C | 16.7°C | 36.6°C | 11.8°C | 8 mm | 23% | 2.2 m/s | 6.8 |
| 2019 | 32.9°C | 24.6°C | 16.3°C | 35.2°C | 12.1°C | 7 mm | 30% | 1.9 m/s | 6.8 |
| 2018 | 31.4°C | 23.6°C | 15.8°C | 36.0°C | 11.1°C | 45 mm | 36% | 2.2 m/s | 6.5 |
| 2017 | 30.2°C | 22.4°C | 14.6°C | 34.6°C | 11.5°C | 28 mm | 41% | 1.7 m/s | 6.5 |
| 2016 | 29.1°C | 21.4°C | 13.7°C | 35.4°C | 8.8°C | 33 mm | 43% | 1.9 m/s | 6.3 |
| 2015 | 30.0°C | 22.4°C | 14.8°C | 34.3°C | 10.3°C | 35 mm | 43% | 2.1 m/s | 6.3 |
| 2014 🌧️ | 27.6°C | 20.5°C | 13.4°C | 32.9°C | 9.1°C | 75 mm | 51% | 1.9 m/s | 6 |
| 2013 | 29.2°C | 21.8°C | 14.4°C | 33.8°C | 10.7°C | 43 mm | 51% | 1.7 m/s | 5.9 |
| 2012 | 31.4°C | 23.5°C | 15.6°C | 35.9°C | 12.6°C | 31 mm | 40% | 1.8 m/s | 6.1 |
| 2011 | 32.3°C | 24.0°C | 15.7°C | 36.5°C | 12.2°C | 28 mm | 37% | 1.9 m/s | 6.8 |
| 2010 | 28.7°C | 21.2°C | 13.6°C | 33.1°C | 9.0°C | 51 mm | 47% | 2.3 m/s | 6.5 |
| 2009 | 30.6°C | 22.3°C | 14.0°C | 35.7°C | 9.2°C | 11 mm | 28% | 2.3 m/s | 6.9 |
| 2008 | 30.4°C | 22.4°C | 14.5°C | 36.4°C | 9.3°C | 37 mm | 36% | 2 m/s | 6.7 |
| 2007 | 30.6°C | 23.2°C | 15.7°C | 35.5°C | 12.1°C | 52 mm | 45% | 1.8 m/s | 6.5 |
| 2006 | 28.9°C | 21.5°C | 14.0°C | 32.4°C | 7.6°C | 43 mm | 46% | 1.7 m/s | 6.3 |
| 2005 | 28.2°C | 21.2°C | 14.2°C | 32.9°C | 7.3°C | 39 mm | 46% | 1.7 m/s | 6.3 |
| 2004 | 29.4°C | 21.5°C | 13.5°C | 34.2°C | 7.0°C | 21 mm | 34% | 2.1 m/s | 6.5 |
| 2003 | 30.4°C | 23.1°C | 15.9°C | 36.6°C | 10.2°C | 28 mm | 43% | 1.8 m/s | 6.4 |
| 2002 | 30.7°C | 22.5°C | 14.3°C | 35.7°C | 10.7°C | 22 mm | 28% | 2.4 m/s | 6.7 |
| 2001 | 29.3°C | 21.9°C | 14.4°C | 33.9°C | 10.2°C | 52 mm | 47% | 1.7 m/s | 6.3 |
| 2000 | 31.2°C | 23.7°C | 16.1°C | 38.0°C | 10.0°C | 42 mm | 41% | 2.2 m/s | 6.4 |
| 1999 | 27.2°C | 20.3°C | 13.4°C | 31.6°C | 10.3°C | 60 mm | 54% | 1.8 m/s | 5.9 |
| 1998 | 30.6°C | 22.7°C | 14.8°C | 34.1°C | 11.0°C | 20 mm | 39% | 1.9 m/s | 6.8 |
| 1997 | 28.3°C | 21.2°C | 14.1°C | 32.9°C | 10.3°C | 63 mm | 51% | 1.9 m/s | 6.3 |
| 1996 | 31.4°C | 23.1°C | 14.7°C | 37.0°C | 11.5°C | 13 mm | 30% | 2.1 m/s | 6.8 |
| 1995 | 31.1°C | 23.1°C | 15.2°C | 35.0°C | 10.7°C | 34 mm | 40% | 2 m/s | 6.9 |
| 1994 | 31.0°C | 23.5°C | 15.9°C | 36.2°C | 12.2°C | 34 mm | 39% | 2 m/s | 6 |
| 1993 | 28.0°C | 20.6°C | 13.2°C | 33.4°C | 9.8°C | 55 mm | 44% | 2.2 m/s | 6.3 |
| 1992 | 29.4°C | 21.6°C | 13.8°C | 34.3°C | 4.9°C | 32 mm | 41% | 2 m/s | 6.3 |
| 1991 | 29.3°C | 21.8°C | 14.3°C | 32.7°C | 11.4°C | 31 mm | 43% | 1.8 m/s | 6.2 |
| 1990 | 30.3°C | 21.9°C | 13.5°C | 35.3°C | 10.4°C | 24 mm | 33% | 2.2 m/s | 6.6 |
| 1989 | 28.7°C | 20.6°C | 12.5°C | 33.1°C | 7.9°C | 35 mm | 40% | 2.3 m/s | 6.6 |
| 1988 | 30.2°C | 22.3°C | 14.5°C | 33.6°C | 11.6°C | 38 mm | 41% | 1.9 m/s | 6.5 |
| 1987 ❄️ | 27.9°C | 20.3°C | 12.7°C | 32.7°C | 7.5°C | 48 mm | 45% | 1.9 m/s | 6.6 |
| 1986 | 30.2°C | 22.6°C | 15.0°C | 35.2°C | 11.9°C | 34 mm | 40% | 1.8 m/s | 6.2 |
| 1985 | 30.9°C | 22.1°C | 13.3°C | 34.5°C | 7.5°C | 5 mm | 27% | 2.2 m/s | 7 |
| 1984 | 29.0°C | 21.8°C | 14.6°C | 32.9°C | 11.3°C | 50 mm | 49% | 1.7 m/s | 6 |
| 1983 | 29.7°C | 22.5°C | 15.2°C | 33.8°C | 11.7°C | 33 mm | 48% | 1.6 m/s | — |
| 1982 | 28.2°C | 21.5°C | 14.7°C | 34.3°C | 10.9°C | 46 mm | 52% | 1.7 m/s | — |
| 1981 | 29.9°C | 21.9°C | 14.0°C | 36.4°C | 10.8°C | 42 mm | 39% | 1.8 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 30.1°C with lows near 14.6°C (mean 22.4°C), based on 45 years of NASA POWER data.
August averages 36 mm of rainfall in Grand Junction, about average for rainfall. The wettest on record was 75 mm in 2014.
The hottest August reached 38°C in 2000. The coldest dipped to 4.9°C in 1992.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 1.3°C. Daytime highs moved from 29.5°C to 30.9°C and overnight lows from 14.4°C to 15.7°C over the same span.
August is one of the warmer months of the year in Grand Junction and about average for rainfall, so plan for around 30.1°C daytime highs and 14.6°C at night.
Not quite — August is the 11th coolest month in Grand Junction, averaging 22.4°C.
For August in Grand Junction, pack light, breathable clothing and sun protection, with typical highs of 30.1°C and lows of 14.6°C.
Relative humidity in August averages 41% — relatively dry.
Average wind speed in August is 2 m/s. The windiest August on record averaged 2.4 m/s (2002).
The wettest August on record was 2014 with 75 mm. On average, August sees 36 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 Grand Junction behaves each August, 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 August specifically, along with year-by-year records and how the month has changed over the decades.
