Big Arm State Park Weather Forecast
- 52
- 61
Slight Chance Rain
- 54
- 71
Becoming Sunny
- 53
- 73
Mostly Sunny
- 54
- 75
Mostly Sunny
- 55
- 75
Partly Sunny
- 54
- 74
Partly Sunny
- 49
- 66
Slight Chance Rain
Today 15 Sep Flathead/Mission Valleys
Rain Showers likely in the Morning, then chance of rain Showers in the afternoon. Slight chance of Thunderstorms early in the afternoon. Chance of precipitation 60 percent. Highs in the 60s.
Tonight 15 Sep Flathead/Mission Valleys
Mostly cloudy. Patchy fog in the late evening and overnight. A 20 percent chance of rain late in the evening. Lows in the 40s.
Big Arm State Park Temperature Statistics
September Temperature
Kalispell, Glacier Park International Airport (33.6 miles)
Lowest 9 September, 2025
44.1 °FAverage September
67.6 °FHighest 2 September, 2025
93.2 °F
Climate (2020–Present)
Kalispell, Glacier Park International Airport (33.6 miles)
Average Low 2020–2025
33.1 °FAverage 2020–2025
45.2 °FAverage High 2020–2025
56.8 °F