July is one of the warmer months of the year in Helena, with average highs near 26.2°C and lows around 10.3°C (mean 18.3°C). It is about average for rainfall, averaging 41 mm of rainfall and 55% relative humidity across the period.
July is one of the warmer months of the year in Helena. Across 45 years of records, the warmest July in Helena was 2007 — when the month averaged 22.2°C — while the coldest was 1993 at 11.7°C. Typical July days reach 26.2°C with nights near 10.3°C. The long-term trend is warming, about 0.6°C per decade.
July is about average for rainfall in Helena, averaging 41 mm of rainfall. The wettest July on record was 1993 with 124 mm, while the driest was 2018 at 9 mm.
Relative humidity in Helena during July averages 55%. The most humid July was 1993 at 71%, and the least humid was 1985 at 42%.
July receives about 7.1 kWh/m²/day of solar energy in Helena. The sunniest Julys were 1996 and 2003 at 7.8 kWh/m²/day, and the cloudiest was 1993 at 5.5.
Average wind speed in Helena during July is 1.1 m/s. The windiest Julys were 1983 and 1999 at 1.3 m/s, while the calmest were 2012 and 2021 at 0.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 17.6°C | 16.8°C | 19.3°C | 18.5°C | 19.6°C | +2°C |
| Avg High | 25.8°C | 24.4°C | 27.6°C | 26.3°C | 27.4°C | +1.6°C |
| Avg Low | 9.4°C | 9.1°C | 11.0°C | 10.7°C | 11.9°C | +2.5°C |
| Avg Rain | 49 mm | 50 mm | 36 mm | 34 mm | 31 mm | -18 mm |
July temperatures in Helena have risen by about 2.7°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 0°C (1981) to a record high of 37.5°C (2002).
Rainfall in July is about average for rainfall, averaging 41 mm, with a wettest year of 124 mm.
One of the best times to visit Helena
July is one of the best times to visit Helena. Expect days averaging 26.2°C and nights around 10.3°C (mean 18.3°C) — warmer than Helena's yearly average — with moderate rainfall (41 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 | 26.4°C | 19.0°C | 11.6°C | 32.0°C | 7.1°C | 47 mm | 56% | 1.1 m/s | 6.9 |
| 2024 | 28.1°C | 20.5°C | 12.8°C | 34.5°C | 6.7°C | 16 mm | 49% | 1.1 m/s | 7.2 |
| 2023 | 26.6°C | 19.0°C | 11.5°C | 32.8°C | 5.1°C | 25 mm | 56% | 1.1 m/s | 7.3 |
| 2022 | 28.6°C | 20.4°C | 12.3°C | 34.6°C | 7.3°C | 50 mm | 54% | 1 m/s | 7.2 |
| 2021 | 30.1°C | 21.9°C | 13.7°C | 34.2°C | 9.7°C | 25 mm | 49% | 0.9 m/s | 6.9 |
| 2020 | 24.4°C | 16.8°C | 9.3°C | 31.0°C | 2.7°C | 23 mm | 61% | 1.2 m/s | 7.5 |
| 2019 | 24.5°C | 17.2°C | 9.9°C | 30.7°C | 4.3°C | 49 mm | 63% | 1 m/s | 6.8 |
| 2018 | 25.6°C | 18.0°C | 10.3°C | 32.0°C | 3.0°C | 9 mm | 60% | 1 m/s | 7.7 |
| 2017 | 29.6°C | 21.4°C | 13.2°C | 33.5°C | 9.0°C | 26 mm | 51% | 1 m/s | 7.6 |
| 2016 | 25.7°C | 17.6°C | 9.5°C | 31.4°C | 1.9°C | 38 mm | 54% | 1.2 m/s | 7.1 |
| 2015 | 24.7°C | 17.6°C | 10.6°C | 31.4°C | 5.0°C | 53 mm | 57% | 1.2 m/s | 6.5 |
| 2014 | 26.6°C | 18.8°C | 11.1°C | 30.5°C | 5.5°C | 33 mm | 59% | 1.1 m/s | 7.4 |
| 2013 | 28.7°C | 20.1°C | 11.5°C | 34.7°C | 8.1°C | 18 mm | 49% | 1 m/s | 7.7 |
| 2012 | 28.5°C | 20.4°C | 12.3°C | 32.6°C | 3.9°C | 39 mm | 55% | 0.9 m/s | 7 |
| 2011 | 25.5°C | 17.6°C | 9.6°C | 31.0°C | 3.7°C | 29 mm | 61% | 1.2 m/s | 7.5 |
| 2010 | 23.7°C | 16.2°C | 8.6°C | 29.5°C | 2.7°C | 42 mm | 62% | 1.2 m/s | 7.2 |
| 2009 | 24.5°C | 16.9°C | 9.3°C | 32.1°C | 2.7°C | 78 mm | 59% | 1 m/s | 6.9 |
| 2008 | 26.0°C | 17.9°C | 9.7°C | 31.4°C | 5.4°C | 28 mm | 53% | 1.1 m/s | 7.4 |
| 2007 🔥 | 30.8°C | 22.2°C | 13.5°C | 35.7°C | 7.5°C | 31 mm | 50% | 1 m/s | 7.3 |
| 2006 | 29.0°C | 20.4°C | 11.9°C | 34.3°C | 5.7°C | 20 mm | 49% | 1.1 m/s | 7.6 |
| 2005 | 27.0°C | 18.6°C | 10.2°C | 32.3°C | 4.1°C | 18 mm | 52% | 1.2 m/s | 7.5 |
| 2004 | 26.3°C | 18.3°C | 10.3°C | 32.4°C | 3.5°C | 41 mm | 55% | 1.1 m/s | 7.1 |
| 2003 | 29.7°C | 21.0°C | 12.3°C | 35.3°C | 6.9°C | 13 mm | 45% | 1.1 m/s | 7.8 |
| 2002 | 28.5°C | 20.0°C | 11.5°C | 37.5°C | 4.7°C | 41 mm | 52% | 1.2 m/s | 7.1 |
| 2001 | 26.6°C | 18.6°C | 10.5°C | 31.9°C | 6.7°C | 61 mm | 54% | 1.1 m/s | 6.5 |
| 2000 | 27.8°C | 19.4°C | 11.0°C | 34.8°C | 6.0°C | 31 mm | 47% | 1 m/s | 6.9 |
| 1999 | 25.6°C | 16.9°C | 8.1°C | 32.4°C | 0.1°C | 14 mm | 50% | 1.3 m/s | 7.4 |
| 1998 | 26.6°C | 19.3°C | 12.0°C | 33.2°C | 8.1°C | 56 mm | 62% | 1 m/s | 7.4 |
| 1997 | 23.1°C | 16.0°C | 8.8°C | 29.2°C | 1.8°C | 66 mm | 67% | 1.1 m/s | 7 |
| 1996 | 26.0°C | 17.9°C | 9.8°C | 32.3°C | 4.0°C | 25 mm | 56% | 1.1 m/s | 7.8 |
| 1995 | 24.0°C | 16.6°C | 9.1°C | 30.8°C | 4.0°C | 81 mm | 63% | 1.2 m/s | 6.5 |
| 1994 | 25.7°C | 17.9°C | 10.2°C | 32.1°C | 2.6°C | 42 mm | 52% | 1.1 m/s | 6.8 |
| 1993 ❄️ 🌧️ | 17.7°C | 11.7°C | 5.6°C | 30.5°C | 2.8°C | 124 mm | 71% | 1.1 m/s | 5.5 |
| 1992 | 22.3°C | 15.1°C | 7.9°C | 29.4°C | 4.1°C | 42 mm | 59% | 1.1 m/s | 6.6 |
| 1991 | 26.8°C | 18.4°C | 9.9°C | 32.6°C | 4.7°C | 19 mm | 51% | 1.2 m/s | 7.6 |
| 1990 | 26.2°C | 17.9°C | 9.6°C | 32.4°C | 4.9°C | 33 mm | 53% | 1.2 m/s | 7.1 |
| 1989 | 28.9°C | 20.0°C | 11.1°C | 34.2°C | 6.5°C | 57 mm | 53% | 1.1 m/s | 7 |
| 1988 | 28.4°C | 19.3°C | 10.3°C | 34.1°C | 1.9°C | 16 mm | 43% | 1.2 m/s | 7.3 |
| 1987 | 24.2°C | 16.5°C | 8.8°C | 32.3°C | 2.8°C | 96 mm | 57% | 1.1 m/s | 6.1 |
| 1986 | 23.1°C | 15.2°C | 7.2°C | 32.2°C | 1.3°C | 61 mm | 54% | 1.2 m/s | 6.7 |
| 1985 | 29.1°C | 20.7°C | 12.2°C | 34.2°C | 7.3°C | 12 mm | 42% | 1 m/s | 7.3 |
| 1984 | 25.9°C | 17.9°C | 9.8°C | 31.5°C | 5.8°C | 19 mm | 54% | 1.1 m/s | 7.1 |
| 1983 | 23.9°C | 15.9°C | 7.8°C | 31.4°C | 1.4°C | 92 mm | 61% | 1.3 m/s | — |
| 1982 | 23.8°C | 16.4°C | 9.0°C | 31.2°C | 1.3°C | 41 mm | 60% | 1.2 m/s | — |
| 1981 | 25.0°C | 16.7°C | 8.4°C | 32.3°C | 0.0°C | 46 mm | 56% | 1.2 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 26.2°C with lows near 10.3°C (mean 18.3°C), based on 45 years of NASA POWER data.
July averages 41 mm of rainfall in Helena, about average for rainfall. The wettest on record was 124 mm in 1993.
The hottest July reached 37.5°C in 2002. The coldest dipped to 0°C in 1981.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 2.7°C. Daytime highs moved from 25.5°C to 28°C and overnight lows from 9.4°C to 12.4°C over the same span.
July is one of the warmer months of the year in Helena and about average for rainfall, so plan for around 26.2°C daytime highs and 10.3°C at night.
Not quite — July is the 12th coolest month in Helena, averaging 18.3°C.
For July in Helena, pack light layers you can adjust through the day, with typical highs of 26.2°C and lows of 10.3°C.
Relative humidity in July averages 55% — moderately humid.
Average wind speed in July is 1.1 m/s. The windiest July on record averaged 1.3 m/s (1983).
The wettest July on record was 1993 with 124 mm. On average, July sees 41 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 Helena 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.
