Big Sky Weather Forecast
- 39
- 52
Rain Showers Likely
- 40
- 61
Mostly Sunny
- 43
- 64
Sunny
- 46
- 66
Mostly Sunny
- 45
- 66
Partly Sunny
- 40
- 61
Partly Sunny
Today 16 Sep Gallatin and Madison County Mountains and Centennial Mountains
Mostly cloudy. Chance of rain in the Morning, then chance of rain Showers and slight chance of Thunderstorms in the afternoon. Highs 50 to 60. North Winds 5 to 15 Mph. Chance of precipitation 50 percent.
Tonight 16 Sep Gallatin and Madison County Mountains and Centennial Mountains
Partly cloudy. Lows 35 to 40. Northeast Winds up to 10 Mph.
Big Sky Temperature Statistics
September Temperature
Ennis - Big Sky Airport (13.7 miles)
Lowest 5 September, 2025
39.2 °FAverage September
61.7 °FHighest 2 September, 2025
87.8 °F
Climate (2020–Present)
Ennis - Big Sky Airport (13.7 miles)
Average Low 2020–2025
31.3 °FAverage 2020–2025
43.7 °FAverage High 2020–2025
55.7 °F