Granite State Park Weather Forecast
- 44
- 64
Increasing Clouds
- 43
- 65
Partly Sunny
- 43
- 65
Mostly Sunny
- 36
- 55
Slight Chance Thunderstorms
- 41
- 58
Mostly Sunny
- 43
- 66
Mostly Sunny
Today 18 Sep Butte/Blackfoot Region
Mostly sunny. Patchy fog in the morning. Highs in the 70s.
Tonight 18 Sep Butte/Blackfoot Region
Mostly clear. Lows in the 40s.
Granite State Park Temperature Statistics
September Temperature
Butte, Bert Mooney Airport (43.5 miles)
Lowest 12 September, 2025
37 °FAverage September
58.7 °FHighest 3 September, 2025
88 °F
Climate (2020–Present)
Butte, Bert Mooney Airport (43.5 miles)
Average Low 2020–2025
27.7 °FAverage 2020–2025
41.6 °FAverage High 2020–2025
55 °F