Weather in Big Sky: September
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Average day temperature: | 65.9°F |
| Average night temperature: | 48.1°F | |
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Number of sunny days: | 19 days |
| Day length: | 11.7 - 13.2 hours | |
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Number of rainy days: | 2 days |
| Precipitation totals: | 1.3 in. | |
| more information | ||
14 days
forecast
forecast
| Big Sky |
weather in
October
October
| Big Sky |
Air temperature in September, °F
Show year:
2026
2025
2024
The highest day temperature during September of 2026 was 67°F. At the same time the lowest night temperature was 31°F. Daily and nightly averages during September were 59.1°F and 40.0°F.
Sunny, partly cloudy and cloudy days
Mostly all days in September are sunny but cloudy days are also possible.
Precipitation total in September, in.
Precipitation total value in Big Sky in September is 1.3 in. Other months of the year show relatively similar values.
Wind speed in September, mph
The average wind speed value in September is 5.3 mph It makes September one of the most windy months of the year.
Average sunny hours
This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 8.7.
Best time for vacation in Big Sky
Big Sky on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Big Sky
Local time: 10:42
October 29, thursday
1200
37°F
N
5 mph
5 mph
1500
41°F
N
5 mph
5 mph
1800
34°F
N
2 mph
2 mph
2100
30°F
N
2 mph
2 mph
October 30, friday
0000
30°F
N
2 mph
2 mph
0300
28°F
NW
2 mph
2 mph
0600
30°F
NW
2 mph
2 mph
0900
32°F
NW
2 mph
2 mph
