September weather forecastBig Sky Colonial Manor, MT
September
Weather in September
September, the first month of the autumn in Big Sky Colonial Manor, is still a comfortable month, with temperature in the range of an average low of 39.2°F (4°C) and an average high of 65.5°F (18.6°C).Temperature
September's onset corresponds with a shift in the average high-temperature, moving from a warm 76.8°F (24.9°C) in August to a comfortable 65.5°F (18.6°C). Big Sky Colonial Manor demonstrates a significant disparity from daytime highs throughout the month of September, with an average nighttime temperature of 39.2°F (4°C).Humidity
The average relative humidity in September is 64%.Rainfall
In September, in Big Sky Colonial Manor, the rain falls for 8.5 days. Throughout September, 0.71" (18mm) of precipitation is accumulated. Throughout the year, there are 126.4 rainfall days, and 11.22" (285mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.3 snowfall days, it receives 0.04" (1mm) of snow. Throughout the year, there are 97 snowfall days, and 33.86" (860mm) of snow is accumulated.Daylight
In September, the average length of the day is 12h and 34min.On the first day of the month, sunrise is at 6:55 am and sunset at 8:17 pm. On the last day of September, sunrise is at 7:35 am and sunset at 7:17 pm MDT.
Sunshine
In September, the average sunshine is 9.4h.UV index
The average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A maximum daily UV index of 3 during September morphs into the following directions:
Be vigilant - Suggestions to stave off sun damage are provided. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Always opt for UVA and UVB-resistant sunglasses on radiant days. Take warning! The intensity of the Sun's UV radiation can be nearly amplified twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Big Sky Colonial Manor, MT
- Average high temperature in September: 65.5°F
The warmest month (with the highest average high temperature) is July (77.9°F).
The month with the lowest average high temperature is December (25.7°F).
- Average low temperature in September: 39.2°F
The month with the highest average low temperature is August (45.5°F).
The coldest month (with the lowest average low temperature) is February (13.5°F).
Average pressure in September
Big Sky Colonial Manor, MT
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Big Sky Colonial Manor, MT
- Average wind speed in September: 3.8mph
The windiest month (with the highest average wind speed) is April (4.6mph).
The calmest months (with the lowest average wind speed) are August and December (3.7mph).
Average humidity in September
Big Sky Colonial Manor, MT
- Average humidity in September: 64%
The month with the highest relative humidity is January (93%).
The month with the lowest relative humidity is August (55%).
Average rainfall in September
Big Sky Colonial Manor, MT
- Average rainfall in September: 0.71"
The wettest month (with the highest rainfall) is June (1.42").
The driest month (with the least rainfall) is August (0.43").
Average rainfall days in September
Big Sky Colonial Manor, MT
- Average rainfall days in September: 8.5 days
The month with the highest number of rainy days is April (15.8 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in September
Big Sky Colonial Manor, MT
- Average snowfall in September: 0.04"
The month with the highest snowfall is January (7.72").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Big Sky Colonial Manor, MT
- Average snowfall days in September: 0.3 days
The month with the highest number of snowfall days is December (19.1 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Big Sky Colonial Manor, MT
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 24min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in September
Big Sky Colonial Manor, MT
- Average sunshine days in September: 19 days
The month with the most sunshine days is July (21.5 days).
The month with the least sunshine days is March (7.7 days).
Average UV index in September
Big Sky Colonial Manor, MT
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in September
Big Sky Colonial Manor, MT
- Average cloud cover in September: 24
The month with the most cloud cover is January (Cloud cover 65).
The months with the least cloud cover are July and August (Cloud cover 15).
Average visibility in September
Big Sky Colonial Manor, MT
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The month with the lowest visibility is January (3mi).
