July is one of the warmer months of the year in Boise, with average highs near 32.8°C and lows around 16.7°C (mean 24.8°C). It is one of the drier months, averaging 8 mm of rainfall and 33% relative humidity across the period.
July is one of the warmer months of the year in Boise. Across 45 years of records, the warmest July in Boise was 2021 — when the month averaged 28.8°C — while the coldest was 1993 at 17.8°C. Typical July days reach 32.8°C with nights near 16.7°C. The long-term trend is warming, about 0.9°C per decade.
July is one of the drier months in Boise, averaging 8 mm of rainfall. The wettest July on record was 1983 with 28 mm, while the driest was 2022 at 0 mm.
Relative humidity in Boise during July averages 33%. The most humid July was 1982 at 46%, and the least humid was 2013 at 23%.
July receives about 7.7 kWh/m²/day of solar energy in Boise. The sunniest Julys were 1999, 2010 and 2020 at 8.1 kWh/m²/day, and the cloudiest were 1984 and 2021 at 7.1.
Average wind speed in Boise during July is 2.1 m/s. The windiest July was 1993 at 2.5 m/s, while the calmest were 2017, 2022 and 2023, among others at 1.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 23.4°C | 23.4°C | 25.8°C | 25.3°C | 26.4°C | +3°C |
| Avg High | 31.5°C | 31.3°C | 34.0°C | 33.3°C | 34.4°C | +2.9°C |
| Avg Low | 15.3°C | 15.4°C | 17.7°C | 17.3°C | 18.4°C | +3.1°C |
| Avg Rain | 13 mm | 9 mm | 7 mm | 6 mm | 8 mm | -4 mm |
July temperatures in Boise have risen by about 3.7°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 5.3°C (1986) to a record high of 43.4°C (2002).
Rainfall in July is one of the drier months, averaging 8 mm, with a wettest year of 28 mm.
One of the best times to visit Boise
July is one of the best times to visit Boise. Expect days averaging 32.8°C and nights around 16.7°C (mean 24.8°C) — warmer than Boise's yearly average — with low rainfall (8 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 | 33.5°C | 25.6°C | 17.7°C | 38.7°C | 13.6°C | 17 mm | 34% | 2.2 m/s | 7.7 |
| 2024 | 35.3°C | 27.3°C | 19.4°C | 41.4°C | 12.8°C | 4 mm | 30% | 2 m/s | 7.5 |
| 2023 | 34.3°C | 26.3°C | 18.3°C | 39.4°C | 13.7°C | 1 mm | 32% | 1.9 m/s | 8 |
| 2022 | 35.1°C | 27.0°C | 18.8°C | 40.2°C | 14.2°C | 0 mm | 32% | 1.9 m/s | 8 |
| 2021 🔥 | 36.7°C | 28.8°C | 20.9°C | 40.5°C | 16.2°C | 19 mm | 26% | 2 m/s | 7.1 |
| 2020 | 31.5°C | 23.4°C | 15.2°C | 39.4°C | 9.1°C | 7 mm | 38% | 2.2 m/s | 8.1 |
| 2019 | 32.0°C | 24.4°C | 16.9°C | 38.5°C | 11.3°C | 4 mm | 37% | 2 m/s | 7.4 |
| 2018 | 34.4°C | 26.2°C | 18.0°C | 39.2°C | 8.2°C | 1 mm | 29% | 2.2 m/s | 8 |
| 2017 | 35.1°C | 27.0°C | 18.9°C | 39.1°C | 15.5°C | 2 mm | 33% | 1.9 m/s | 7.8 |
| 2016 | 31.8°C | 23.7°C | 15.5°C | 37.8°C | 8.1°C | 7 mm | 32% | 2.3 m/s | 8 |
| 2015 | 31.0°C | 24.1°C | 17.2°C | 38.9°C | 10.7°C | 24 mm | 38% | 2 m/s | 7.2 |
| 2014 | 35.0°C | 27.0°C | 19.0°C | 39.3°C | 11.5°C | 4 mm | 30% | 2.2 m/s | 7.5 |
| 2013 | 35.8°C | 27.5°C | 19.1°C | 41.6°C | 13.5°C | 2 mm | 23% | 2.2 m/s | 7.7 |
| 2012 | 35.0°C | 26.6°C | 18.3°C | 40.4°C | 11.7°C | 3 mm | 31% | 2.3 m/s | 7.5 |
| 2011 | 31.6°C | 23.5°C | 15.4°C | 37.6°C | 10.1°C | 4 mm | 37% | 2 m/s | 8 |
| 2010 | 31.7°C | 23.3°C | 14.9°C | 38.5°C | 8.0°C | 7 mm | 35% | 2.2 m/s | 8.1 |
| 2009 | 32.7°C | 24.8°C | 16.8°C | 39.7°C | 11.4°C | 6 mm | 33% | 2 m/s | 7.8 |
| 2008 | 33.1°C | 24.7°C | 16.3°C | 39.2°C | 12.3°C | 8 mm | 30% | 2.3 m/s | 7.9 |
| 2007 | 36.6°C | 28.3°C | 20.1°C | 42.0°C | 15.5°C | 2 mm | 25% | 2.1 m/s | 7.3 |
| 2006 | 35.1°C | 27.0°C | 18.8°C | 41.2°C | 11.6°C | 10 mm | 33% | 2 m/s | 7.8 |
| 2005 | 33.5°C | 25.2°C | 16.8°C | 40.2°C | 12.2°C | 2 mm | 32% | 2.2 m/s | 7.9 |
| 2004 | 32.9°C | 25.1°C | 17.3°C | 39.9°C | 9.6°C | 13 mm | 33% | 2 m/s | 7.8 |
| 2003 | 36.0°C | 27.5°C | 19.0°C | 43.1°C | 12.8°C | 8 mm | 28% | 2.1 m/s | 8 |
| 2002 | 35.1°C | 26.9°C | 18.7°C | 43.4°C | 12.3°C | 3 mm | 27% | 2.2 m/s | 7.6 |
| 2001 | 31.7°C | 24.1°C | 16.4°C | 40.4°C | 9.7°C | 15 mm | 34% | 2.1 m/s | 7.3 |
| 2000 | 32.9°C | 24.6°C | 16.4°C | 39.0°C | 8.0°C | 3 mm | 28% | 2.3 m/s | 7.7 |
| 1999 | 31.7°C | 23.2°C | 14.8°C | 38.8°C | 7.5°C | 1 mm | 28% | 2.3 m/s | 8.1 |
| 1998 | 33.5°C | 25.7°C | 17.9°C | 41.1°C | 14.0°C | 15 mm | 42% | 2 m/s | 7.7 |
| 1997 | 30.5°C | 22.6°C | 14.8°C | 37.2°C | 8.7°C | 16 mm | 41% | 2 m/s | 7.6 |
| 1996 | 33.2°C | 25.1°C | 16.9°C | 38.9°C | 10.8°C | 7 mm | 34% | 2 m/s | 7.7 |
| 1995 | 30.2°C | 22.5°C | 14.8°C | 37.2°C | 8.6°C | 19 mm | 43% | 2.1 m/s | 7.4 |
| 1994 | 33.8°C | 25.7°C | 17.6°C | 40.9°C | 9.1°C | 3 mm | 27% | 2.3 m/s | 7.6 |
| 1993 ❄️ | 25.1°C | 17.8°C | 10.5°C | 36.4°C | 7.7°C | 14 mm | 46% | 2.5 m/s | 7.7 |
| 1992 | 29.9°C | 22.2°C | 14.5°C | 39.1°C | 9.9°C | 3 mm | 36% | 2.2 m/s | 7.6 |
| 1991 | 32.9°C | 24.5°C | 16.2°C | 38.0°C | 12.2°C | 3 mm | 33% | 2.1 m/s | 7.7 |
| 1990 | 32.7°C | 24.4°C | 16.1°C | 39.1°C | 8.4°C | 9 mm | 34% | 2.1 m/s | 7.4 |
| 1989 | 34.3°C | 25.4°C | 16.5°C | 41.2°C | 11.5°C | 3 mm | 28% | 2.1 m/s | 7.6 |
| 1988 | 33.7°C | 25.0°C | 16.3°C | 39.8°C | 9.4°C | 1 mm | 28% | 2.3 m/s | 7.5 |
| 1987 | 29.9°C | 22.1°C | 14.3°C | 38.1°C | 9.4°C | 15 mm | 34% | 2.2 m/s | 7.3 |
| 1986 | 29.2°C | 21.3°C | 13.5°C | 37.1°C | 5.3°C | 4 mm | 34% | 2.2 m/s | 7.6 |
| 1985 | 35.4°C | 27.3°C | 19.2°C | 40.3°C | 14.3°C | 18 mm | 28% | 2.1 m/s | 7.3 |
| 1984 | 31.9°C | 24.2°C | 16.5°C | 38.1°C | 11.2°C | 14 mm | 40% | 2 m/s | 7.1 |
| 1983 🌧️ | 28.8°C | 20.9°C | 13.0°C | 37.9°C | 6.4°C | 28 mm | 43% | 2.2 m/s | — |
| 1982 | 29.0°C | 21.7°C | 14.3°C | 36.8°C | 7.7°C | 24 mm | 46% | 1.9 m/s | — |
| 1981 | 31.3°C | 22.6°C | 14.0°C | 37.4°C | 6.6°C | 7 mm | 33% | 2.3 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 32.8°C with lows near 16.7°C (mean 24.8°C), based on 45 years of NASA POWER data.
July averages 8 mm of rainfall in Boise, one of the drier months. The wettest on record was 28 mm in 1983.
The hottest July reached 43.4°C in 2002. The coldest dipped to 5.3°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 3.7°C. Daytime highs moved from 31.3°C to 35°C and overnight lows from 15.4°C to 19°C over the same span.
July is one of the warmer months of the year in Boise and one of the drier months, so plan for around 32.8°C daytime highs and 16.7°C at night.
Not quite — July is the 12th coolest month in Boise, averaging 24.8°C.
For July in Boise, pack light, breathable clothing and sun protection, with typical highs of 32.8°C and lows of 16.7°C.
Relative humidity in July averages 33% — relatively dry.
Average wind speed in July is 2.1 m/s. The windiest July on record averaged 2.5 m/s (1993).
The wettest July on record was 1983 with 28 mm. On average, July sees 8 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 Boise 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.
