Cool
Average highs are around 18°C, so pack for cooler days.
September verdict
Big Sky, Montana, United States in September
Weather score43Mixed
Mixed for holiday weather
Average highs are around 18°C, so pack for cooler days. Sunshine averages 8.4h per day, so bright days are a strong part of the month. Rainfall averages 48mm, which is relatively low for holiday planning.
September weather
Monthly averages
Temp
18°C
Rain
48mm
Sun
8.4h
Weather score
43
Mixed
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
Weather scoreWeather score
Trip feel
Drier
Rainfall averages 48mm, which is relatively low for holiday planning.
Bright
Sunshine averages 8.4h per day, so bright days are a strong part of the month.
Map
Weather map
Compare Big Sky, Montana, United States with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
September18°C average high
September sits in the warmer part of the year, so midday sightseeing can feel heavier than in cooler months.
Warmest monthsJune to September
This stretch sets the upper range for average daytime heat.
Rain
September48mm average rain
September sits on the drier side of Big Sky's year, which helps with sightseeing and transfers.
Driest monthsJanuary to May and July to December
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
September8.4 hours average sun
September sits close to Big Sky's yearly sunshine average, so it is a middle-of-the-pack month for bright days.
Brightest monthsJune to August
This stretch has the strongest sunshine in the monthly averages.
Weather score
September43 weather score
September sits close to Big Sky's yearly weather-score average, giving a typical overall read on the month.
Best weather monthsJuly to August
These months have the strongest weather score in the monthly averages.
