September weather forecastSunburst, MT
September
Weather in September
September, the first month of the autumn in Sunburst, is also an agreeable month, with an average temperature varying between 50.7°F (10.4°C) and 68.9°F (20.5°C).Temperature
The start of September signals a decrease in the average high-temperature, transitioning from a warm 79.9°F (26.6°C) in August to a pleasant 68.9°F (20.5°C). During September, the average low-temperature is recorded at a cool 50.7°F (10.4°C).Humidity
The average relative humidity in September is 46%.Rainfall
In Sunburst, during September, the rain falls for 6.5 days and regularly aggregates up to 0.59" (15mm) of precipitation. In Sunburst, during the entire year, the rain falls for 84.2 days and collects up to 9.29" (236mm) of precipitation.Snowfall
Months with snowfall are January through May, September through December. September is the first month it typically snows. Throughout September, in the average 0.9 snowfall days, it receives 0.63" (16mm) of snow. Throughout the year, there are 53.7 snowfall days, and 20.47" (520mm) of snow is accumulated.Daylight
In Sunburst, the average length of the day in September is 12h and 34min.On the first day of the month, sunrise is at 6:45 am and sunset at 8:09 pm. On the last day of September, sunrise is at 7:26 am and sunset at 7:07 pm MDT.
Sunshine
In September, the average sunshine is 9.7h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: A daily maximum UV index of 4 in September translates into the following instructions:
Guard yourself - An obligation to protect skin and eyes from harm exists. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. On your guard! Snow's reflection can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Sunburst, MT
- Average high temperature in September: 68.9°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is December (27.7°F).
- Average low temperature in September: 50.7°F
The month with the highest average low temperature is August (58.3°F).
The coldest month (with the lowest average low temperature) is December (15.4°F).
Average pressure in September
Sunburst, MT
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Sunburst, MT
- Average wind speed in September: 9.4mph
The windiest month (with the highest average wind speed) is April (11mph).
The calmest month (with the lowest average wind speed) is August (8.7mph).
Average humidity in September
Sunburst, MT
- Average humidity in September: 46%
The month with the highest relative humidity is January (80%).
The month with the lowest relative humidity is August (40%).
Average rainfall in September
Sunburst, MT
- Average rainfall in September: 0.59"
The wettest month (with the highest rainfall) is June (2.01").
The driest months (with the least rainfall) are January and December (0.39").
Average rainfall days in September
Sunburst, MT
- Average rainfall days in September: 6.5 days
The month with the highest number of rainy days is May (13.9 days).
The month with the least rainy days is February (3.1 days).
Average snowfall in September
Sunburst, MT
- Average snowfall in September: 0.63"
The month with the highest snowfall is February (4.17").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Sunburst, MT
- Average snowfall days in September: 0.9 days
The month with the highest number of snowfall days is February (10.3 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Sunburst, MT
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 18min).
- Average sunshine in September: 9h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 5h and 24min).
Average sunshine days in September
Sunburst, MT
- Average sunshine days in September: 22.2 days
The month with the most sunshine days is September (22.2 days).
The month with the least sunshine days is April (14.7 days).
Average UV index in September
Sunburst, MT
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in September
Sunburst, MT
- Average cloud cover in September: 23
The month with the most cloud cover is February (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 15).
Average visibility in September
Sunburst, MT
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





