June is one of the warmer months of the year in Helena, with average highs near 20.5°C and lows around 6.1°C (mean 13.3°C). It is a relatively wet time of year, averaging 73 mm of rainfall and 63% relative humidity across the period.
June is one of the warmer months of the year in Helena. Across 45 years of records, the warmest June in Helena was 1988 — when the month averaged 17.8°C — while the coldest was 1998 at 10.2°C. Typical June days reach 20.5°C with nights near 6.1°C. The long-term trend is warming, about 0.2°C per decade.
June is a relatively wet time of year in Helena, averaging 73 mm of rainfall. The wettest June on record was 2020 with 163 mm, while the driest was 1985 at 15 mm.
Relative humidity in Helena during June averages 63%. The most humid June was 1998 at 72%, and the least humid was 1985 at 49%.
June receives about 6.4 kWh/m²/day of solar energy in Helena. The sunniest June was 2021 at 7.7 kWh/m²/day, and the cloudiest was 1993 at 5.3.
Average wind speed in Helena during June is 1.3 m/s. The windiest Junes were 1981 and 1993 at 1.5 m/s, while the calmest was 2023 at 0.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 13.7°C | 12.6°C | 13.0°C | 13.2°C | 14.2°C | +0.5°C |
| Avg High | 21.3°C | 19.7°C | 20.4°C | 20.2°C | 21.3°C | 0°C |
| Avg Low | 6.1°C | 5.5°C | 5.7°C | 6.3°C | 7.0°C | +0.9°C |
| Avg Rain | 54 mm | 79 mm | 79 mm | 76 mm | 79 mm | +25 mm |
June temperatures in Helena have risen by about 2.3°C between 1981–1985 and 2021–2025.
June has ranged from a record low of -3.3°C (2000) to a record high of 35.1°C (1988).
Rainfall in June is a relatively wet time of year, averaging 73 mm, with a wettest year of 163 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0°C per decade while lows rose 0.3°C per decade, narrowing the gap between day and night.
One of the best times to visit Helena
June is one of the best times to visit Helena. Expect days averaging 20.5°C and nights around 6.1°C (mean 13.3°C) — warmer than Helena's yearly average — with moderate rainfall (73 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 | 21.9°C | 14.8°C | 7.8°C | 29.3°C | -0.6°C | 37 mm | 58% | 1.1 m/s | 6.7 |
| 2024 | 21.9°C | 14.1°C | 6.4°C | 29.9°C | 0.0°C | 58 mm | 59% | 1.4 m/s | 7 |
| 2023 | 19.0°C | 13.2°C | 7.3°C | 25.8°C | 0.8°C | 133 mm | 72% | 0.9 m/s | 5.7 |
| 2022 | 20.1°C | 13.0°C | 6.0°C | 30.8°C | 2.0°C | 68 mm | 63% | 1.4 m/s | 6 |
| 2021 | 26.0°C | 17.4°C | 8.8°C | 33.8°C | -0.3°C | 16 mm | 53% | 1.3 m/s | 7.7 |
| 2020 🌧️ | 19.1°C | 12.5°C | 5.8°C | 28.6°C | -1.3°C | 163 mm | 69% | 1.3 m/s | 5.7 |
| 2019 | 19.3°C | 12.8°C | 6.2°C | 26.0°C | 0.2°C | 42 mm | 67% | 1.2 m/s | 6.5 |
| 2018 | 19.0°C | 12.7°C | 6.5°C | 28.0°C | -2.3°C | 132 mm | 71% | 1.3 m/s | 6.1 |
| 2017 | 21.1°C | 13.8°C | 6.6°C | 30.9°C | -0.4°C | 69 mm | 63% | 1.4 m/s | 6.8 |
| 2016 | 23.4°C | 15.5°C | 7.6°C | 29.5°C | 2.5°C | 41 mm | 58% | 1.3 m/s | 7.4 |
| 2015 | 23.6°C | 16.7°C | 9.8°C | 33.6°C | 3.5°C | 39 mm | 61% | 1 m/s | 7.3 |
| 2014 | 17.5°C | 11.2°C | 4.9°C | 21.8°C | 0.9°C | 83 mm | 69% | 1.3 m/s | 6.4 |
| 2013 | 21.3°C | 13.7°C | 6.1°C | 30.8°C | 0.6°C | 68 mm | 64% | 1.2 m/s | 6.6 |
| 2012 | 21.2°C | 13.4°C | 5.6°C | 30.3°C | 1.4°C | 47 mm | 61% | 1.4 m/s | 6.7 |
| 2011 | 17.8°C | 11.1°C | 4.5°C | 29.0°C | -0.2°C | 112 mm | 70% | 1.3 m/s | 5.9 |
| 2010 | 18.0°C | 11.4°C | 4.9°C | 27.2°C | -0.6°C | 122 mm | 71% | 1.2 m/s | 6 |
| 2009 | 18.8°C | 11.7°C | 4.7°C | 27.5°C | -2.2°C | 68 mm | 65% | 1.1 m/s | 6.2 |
| 2008 | 18.8°C | 11.8°C | 4.7°C | 31.5°C | -1.7°C | 82 mm | 64% | 1.4 m/s | 6.9 |
| 2007 | 22.4°C | 14.5°C | 6.6°C | 31.5°C | 1.3°C | 59 mm | 61% | 1.3 m/s | 6.9 |
| 2006 | 22.1°C | 14.6°C | 7.2°C | 29.9°C | 1.0°C | 99 mm | 63% | 1.3 m/s | 6.8 |
| 2005 | 18.4°C | 11.8°C | 5.3°C | 31.1°C | 0.4°C | 141 mm | 71% | 1.3 m/s | 5.6 |
| 2004 | 19.2°C | 12.3°C | 5.4°C | 26.8°C | 0.4°C | 63 mm | 64% | 1.3 m/s | 6.5 |
| 2003 | 20.8°C | 13.4°C | 6.1°C | 29.7°C | 0.6°C | 47 mm | 62% | 1.2 m/s | 6.9 |
| 2002 | 20.9°C | 13.7°C | 6.5°C | 33.8°C | -0.4°C | 92 mm | 62% | 1.3 m/s | 6.3 |
| 2001 | 20.8°C | 13.1°C | 5.4°C | 29.1°C | -2.4°C | 87 mm | 58% | 1.3 m/s | 6.8 |
| 2000 | 21.5°C | 13.5°C | 5.5°C | 31.4°C | -3.3°C | 49 mm | 57% | 1.4 m/s | 6.9 |
| 1999 | 18.8°C | 11.9°C | 5.0°C | 26.9°C | -1.4°C | 67 mm | 66% | 1.2 m/s | 6.5 |
| 1998 ❄️ | 16.1°C | 10.2°C | 4.3°C | 25.2°C | -0.7°C | 131 mm | 72% | 1.3 m/s | 5.6 |
| 1997 | 19.7°C | 13.4°C | 7.0°C | 27.3°C | 2.9°C | 105 mm | 71% | 1.2 m/s | 6.1 |
| 1996 | 21.0°C | 13.4°C | 5.8°C | 27.8°C | -1.2°C | 41 mm | 63% | 1.3 m/s | 6.9 |
| 1995 | 19.4°C | 12.2°C | 5.0°C | 26.3°C | -1.6°C | 81 mm | 66% | 1.2 m/s | 5.6 |
| 1994 | 21.3°C | 13.3°C | 5.2°C | 29.6°C | -1.1°C | 47 mm | 58% | 1.3 m/s | 6.5 |
| 1993 | 18.0°C | 11.1°C | 4.2°C | 28.6°C | -0.2°C | 103 mm | 67% | 1.5 m/s | 5.3 |
| 1992 | 22.5°C | 15.3°C | 8.2°C | 30.1°C | 0.3°C | 96 mm | 59% | 1.1 m/s | 5.9 |
| 1991 | 19.7°C | 12.6°C | 5.5°C | 26.8°C | -1.6°C | 77 mm | 64% | 1.3 m/s | 6 |
| 1990 | 20.6°C | 12.8°C | 5.0°C | 33.6°C | -2.0°C | 41 mm | 60% | 1.4 m/s | 6.4 |
| 1989 | 20.8°C | 13.2°C | 5.6°C | 30.0°C | 1.1°C | 42 mm | 62% | 1.2 m/s | 6.5 |
| 1988 🔥 | 26.4°C | 17.8°C | 9.2°C | 35.1°C | 1.6°C | 42 mm | 52% | 1.3 m/s | 6.4 |
| 1987 | 23.4°C | 15.3°C | 7.2°C | 31.4°C | -2.0°C | 40 mm | 53% | 1.3 m/s | 6.7 |
| 1986 | 23.9°C | 16.1°C | 8.3°C | 31.8°C | 2.2°C | 67 mm | 58% | 1.2 m/s | 6.7 |
| 1985 | 21.9°C | 13.5°C | 5.1°C | 30.7°C | 0.5°C | 15 mm | 49% | 1.4 m/s | 7.1 |
| 1984 | 19.0°C | 11.6°C | 4.3°C | 32.0°C | -3.1°C | 77 mm | 63% | 1.3 m/s | 6.2 |
| 1983 | 18.8°C | 11.8°C | 4.8°C | 29.0°C | -0.8°C | 77 mm | 65% | 1.2 m/s | — |
| 1982 | 19.5°C | 13.0°C | 6.6°C | 27.7°C | -0.6°C | 73 mm | 67% | 1 m/s | — |
| 1981 | 17.8°C | 10.9°C | 3.9°C | 28.4°C | 0.1°C | 56 mm | 65% | 1.5 m/s | — |
Actual recorded June data for each year, 1981–2025 — sourced from NASA POWER.
The average high in June is around 20.5°C with lows near 6.1°C (mean 13.3°C), based on 45 years of NASA POWER data.
June averages 73 mm of rainfall in Helena, a relatively wet time of year. The wettest on record was 163 mm in 2020.
The hottest June reached 35.1°C in 1988. The coldest dipped to -3.3°C in 2000.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average June temperatures have risen by about 2.3°C. Daytime highs moved from 19.4°C to 21.8°C and overnight lows from 4.9°C to 7.3°C over the same span.
June is one of the warmer months of the year in Helena and a relatively wet time of year, so plan for around 20.5°C daytime highs and 6.1°C at night.
Not quite — June is the 10th coolest month in Helena, averaging 13.3°C.
For June in Helena, pack warm layers and a jacket for chilly mornings, with typical highs of 20.5°C and lows of 6.1°C. Bring an umbrella or light rain jacket too.
Relative humidity in June averages 63% — moderately humid.
Average wind speed in June is 1.3 m/s. The windiest June on record averaged 1.5 m/s (1981).
The wettest June on record was 2020 with 163 mm. On average, June sees 73 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 June, 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 June specifically, along with year-by-year records and how the month has changed over the decades.
