June is one of the warmer months of the year in Great Falls, with average highs near 23°C and lows around 9.2°C (mean 16.1°C). It is a relatively wet time of year, averaging 72 mm of rainfall and 57% relative humidity across the period.
June is one of the warmer months of the year in Great Falls. Across 45 years of records, the warmest June in Great Falls was 1988 — when the month averaged 21.1°C — while the coldest was 1998 at 13.2°C. Typical June days reach 23°C with nights near 9.2°C. The long-term June temperature trend is broadly flat.
June is a relatively wet time of year in Great Falls, averaging 72 mm of rainfall. The wettest June on record was 2005 with 164 mm, while the driest was 2021 at 19 mm.
Relative humidity in Great Falls during June averages 57%. The most humid June was 2005 at 66%, and the least humid were 1985 and 1988 at 46%.
June receives about 6.6 kWh/m²/day of solar energy in Great Falls. The sunniest June was 2021 at 7.6 kWh/m²/day, and the cloudiest were 1993 and 1998 at 5.9.
Average wind speed in Great Falls during June is 2.4 m/s. The windiest Junes were 1981 and 2012 at 2.9 m/s, while the calmest was 1982 at 1.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 16.6°C | 15.4°C | 15.9°C | 16.1°C | 16.9°C | +0.3°C |
| Avg High | 23.9°C | 22.1°C | 22.8°C | 22.8°C | 23.5°C | -0.4°C |
| Avg Low | 9.3°C | 8.7°C | 8.9°C | 9.4°C | 10.2°C | +0.9°C |
| Avg Rain | 52 mm | 81 mm | 80 mm | 71 mm | 76 mm | +23 mm |
June temperatures in Great Falls have risen by about 2.1°C between 1981–1985 and 2021–2025.
June has ranged from a record low of -0.9°C (2000) to a record high of 38.5°C (1988).
Rainfall in June is a relatively wet time of year, averaging 72 mm, with a wettest year of 164 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 Great Falls
June is one of the best times to visit Great Falls. Expect days averaging 23°C and nights around 9.2°C (mean 16.1°C) — warmer than Great Falls's yearly average — with moderate rainfall (72 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 | 23.5°C | 17.0°C | 10.4°C | 32.6°C | 3.3°C | 60 mm | 55% | 2 m/s | 6.6 |
| 2024 | 22.9°C | 16.0°C | 9.0°C | 31.5°C | 3.1°C | 67 mm | 55% | 2.6 m/s | 7.2 |
| 2023 | 22.2°C | 16.4°C | 10.5°C | 29.3°C | 4.7°C | 111 mm | 65% | 1.9 m/s | 6.2 |
| 2022 | 22.9°C | 16.2°C | 9.5°C | 34.9°C | 5.5°C | 58 mm | 55% | 2.6 m/s | 6.1 |
| 2021 | 27.7°C | 19.8°C | 11.9°C | 37.5°C | 5.1°C | 19 mm | 48% | 2.4 m/s | 7.6 |
| 2020 | 22.1°C | 15.8°C | 9.6°C | 32.6°C | 4.0°C | 139 mm | 62% | 2.6 m/s | 6.3 |
| 2019 | 22.5°C | 16.1°C | 9.7°C | 29.1°C | 4.6°C | 51 mm | 59% | 2.3 m/s | 6.5 |
| 2018 | 21.8°C | 15.6°C | 9.5°C | 32.6°C | 3.4°C | 108 mm | 63% | 2.6 m/s | 6.4 |
| 2017 | 24.0°C | 17.1°C | 10.2°C | 34.4°C | 5.1°C | 63 mm | 54% | 2.6 m/s | 6.9 |
| 2016 | 25.9°C | 18.1°C | 10.4°C | 32.2°C | 4.4°C | 39 mm | 49% | 2.4 m/s | 7.3 |
| 2015 | 26.0°C | 19.1°C | 12.2°C | 35.8°C | 6.2°C | 32 mm | 53% | 1.9 m/s | 7.1 |
| 2014 | 20.4°C | 14.4°C | 8.3°C | 26.9°C | 4.9°C | 89 mm | 61% | 2.4 m/s | 6 |
| 2013 | 22.9°C | 16.0°C | 9.2°C | 31.9°C | 1.4°C | 91 mm | 61% | 2.1 m/s | 6.7 |
| 2012 | 23.8°C | 16.4°C | 9.0°C | 34.1°C | 4.1°C | 50 mm | 55% | 2.9 m/s | 6.9 |
| 2011 | 20.4°C | 13.9°C | 7.4°C | 31.6°C | 2.6°C | 97 mm | 64% | 2.5 m/s | 6.2 |
| 2010 | 20.7°C | 14.4°C | 8.1°C | 30.9°C | 2.7°C | 86 mm | 63% | 2.3 m/s | 6.2 |
| 2009 | 22.1°C | 15.1°C | 8.0°C | 29.9°C | 1.2°C | 43 mm | 53% | 2.2 m/s | 6.8 |
| 2008 | 22.1°C | 15.1°C | 8.0°C | 35.7°C | 1.2°C | 76 mm | 55% | 2.5 m/s | 7 |
| 2007 | 25.0°C | 17.5°C | 10.0°C | 34.4°C | 5.3°C | 47 mm | 52% | 2.4 m/s | 7.2 |
| 2006 | 24.0°C | 17.2°C | 10.4°C | 33.6°C | 5.7°C | 115 mm | 59% | 2.4 m/s | 6.9 |
| 2005 🌧️ | 21.0°C | 14.8°C | 8.6°C | 34.0°C | 4.9°C | 164 mm | 66% | 2.3 m/s | 6 |
| 2004 | 21.6°C | 15.0°C | 8.4°C | 30.2°C | 2.6°C | 66 mm | 57% | 2.4 m/s | 6.1 |
| 2003 | 23.3°C | 16.4°C | 9.5°C | 33.6°C | 4.1°C | 54 mm | 55% | 2.3 m/s | 6.6 |
| 2002 | 22.8°C | 16.0°C | 9.2°C | 36.5°C | 1.2°C | 127 mm | 58% | 2.4 m/s | 6.3 |
| 2001 | 23.1°C | 15.9°C | 8.8°C | 31.8°C | 2.0°C | 59 mm | 51% | 2.3 m/s | 6.9 |
| 2000 | 22.9°C | 15.7°C | 8.4°C | 32.7°C | -0.9°C | 54 mm | 54% | 2.4 m/s | 6.6 |
| 1999 | 21.7°C | 15.1°C | 8.6°C | 28.4°C | 2.4°C | 63 mm | 56% | 2.4 m/s | 6.7 |
| 1998 ❄️ | 19.1°C | 13.2°C | 7.4°C | 26.7°C | 1.0°C | 139 mm | 65% | 2.6 m/s | 5.9 |
| 1997 | 22.5°C | 16.1°C | 9.8°C | 32.6°C | 5.7°C | 99 mm | 62% | 2.3 m/s | 6.3 |
| 1996 | 23.2°C | 16.0°C | 8.8°C | 30.7°C | 4.2°C | 46 mm | 56% | 2.4 m/s | 7.1 |
| 1995 | 21.9°C | 15.2°C | 8.6°C | 28.9°C | 2.4°C | 96 mm | 62% | 2 m/s | 6.1 |
| 1994 | 23.5°C | 16.0°C | 8.6°C | 31.2°C | 2.4°C | 44 mm | 53% | 2.4 m/s | 6.9 |
| 1993 | 20.2°C | 13.8°C | 7.5°C | 31.5°C | 1.8°C | 102 mm | 62% | 2.8 m/s | 5.9 |
| 1992 | 24.6°C | 17.8°C | 11.1°C | 32.4°C | 4.3°C | 75 mm | 55% | 2.2 m/s | 6.2 |
| 1991 | 21.9°C | 15.3°C | 8.6°C | 29.8°C | 4.0°C | 108 mm | 60% | 2.4 m/s | 6.3 |
| 1990 | 22.7°C | 15.6°C | 8.4°C | 35.3°C | 2.9°C | 35 mm | 55% | 2.7 m/s | 6.8 |
| 1989 | 23.0°C | 15.9°C | 8.9°C | 33.6°C | 5.4°C | 60 mm | 57% | 2.1 m/s | 6.8 |
| 1988 🔥 | 29.4°C | 21.1°C | 12.7°C | 38.5°C | 5.4°C | 45 mm | 46% | 2.2 m/s | 6.5 |
| 1987 | 26.1°C | 18.3°C | 10.5°C | 34.9°C | 3.4°C | 35 mm | 47% | 2.5 m/s | 7.1 |
| 1986 | 26.2°C | 18.8°C | 11.3°C | 34.1°C | 7.6°C | 61 mm | 53% | 2.3 m/s | 7 |
| 1985 | 23.6°C | 15.7°C | 7.8°C | 32.1°C | 2.6°C | 21 mm | 46% | 2.6 m/s | 7.1 |
| 1984 | 22.6°C | 15.2°C | 7.9°C | 37.2°C | 2.3°C | 56 mm | 54% | 2.4 m/s | 6.3 |
| 1983 | 21.5°C | 14.9°C | 8.4°C | 31.9°C | 4.9°C | 73 mm | 56% | 2.3 m/s | — |
| 1982 | 22.2°C | 15.6°C | 9.0°C | 30.2°C | 2.2°C | 66 mm | 62% | 1.7 m/s | — |
| 1981 | 20.5°C | 13.7°C | 7.0°C | 30.8°C | 1.8°C | 54 mm | 57% | 2.9 m/s | — |
Actual recorded June data for each year, 1981–2025 — sourced from NASA POWER.
The average high in June is around 23°C with lows near 9.2°C (mean 16.1°C), based on 45 years of NASA POWER data.
June averages 72 mm of rainfall in Great Falls, a relatively wet time of year. The wettest on record was 164 mm in 2005.
The hottest June reached 38.5°C in 1988. The coldest dipped to -0.9°C in 2000.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average June temperatures have risen by about 2.1°C. Daytime highs moved from 22.1°C to 23.8°C and overnight lows from 8°C to 10.3°C over the same span.
June is one of the warmer months of the year in Great Falls and a relatively wet time of year, so plan for around 23°C daytime highs and 9.2°C at night.
Not quite — June is the 10th coolest month in Great Falls, averaging 16.1°C.
For June in Great Falls, pack light layers you can adjust through the day, with typical highs of 23°C and lows of 9.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in June averages 57% — moderately humid.
Average wind speed in June is 2.4 m/s. The windiest June on record averaged 2.9 m/s (1981).
The wettest June on record was 2005 with 164 mm. On average, June sees 72 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 Great Falls 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.
