September weather forecastBasin, MT
September
Weather in September
The first month of the autumn, September, is still a refreshing month in Basin, Montana, with an average temperature varying between 42.4°F (5.8°C) and 67.5°F (19.7°C).Temperature
As September commences, the average high-temperature shows a reduction, transitioning from a moderately hot 77.5°F (25.3°C) in August to a refreshing 67.5°F (19.7°C). Basin's average low-temperature of 42.4°F (5.8°C) in September reflects a considerable decline from the daytime peak.Humidity
In Basin, the average relative humidity in September is 52%.Rainfall
In Basin, in September, during 9.8 rainfall days, 1.14" (29mm) of precipitation is typically accumulated. Throughout the year, there are 133.7 rainfall days, and 16.38" (416mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 1.2 snowfall days, it receives 2.01" (51mm) of snow. In Basin, during the entire year, snow falls for 105.8 days and aggregates up to 55.12" (1400mm) of snow.Daylight
In September, the average length of the day in Basin is 12h and 32min.On the first day of September, sunrise is at 6:50 am and sunset at 8:07 pm. On the last day of the month, sunrise is at 7:27 am and sunset at 7:10 pm MDT.
Sunshine
In Basin, Montana, the average sunshine in September is 9.8h.UV index
In Basin, 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 exposure to the Sun's UV radiation for the ordinary person.Note: The UV index of 3 during September leads to these advisories:
Proceed with care. Light skin individuals may be exposed to burns in fewer than 30 minutes. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage. Caution! The reflection of snow can nearly 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
Basin, MT
- Average high temperature in September: 67.5°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is December (27°F).
- Average low temperature in September: 42.4°F
The month with the highest average low temperature is August (48.6°F).
The coldest month (with the lowest average low temperature) is December (12.6°F).
Average pressure in September
Basin, MT
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Basin, MT
- Average wind speed in September: 5.4mph
The windiest months (with the highest average wind speed) are January and November (6.5mph).
The calmest month (with the lowest average wind speed) is August (4.7mph).
Average humidity in September
Basin, MT
- Average humidity in September: 52%
The month with the highest relative humidity is January (86%).
The month with the lowest relative humidity is August (46%).
Average rainfall in September
Basin, MT
- Average rainfall in September: 1.14"
The wettest month (with the highest rainfall) is June (2.68").
The driest month (with the least rainfall) is December (0.79").
Average rainfall days in September
Basin, MT
- Average rainfall days in September: 9.8 days
The month with the highest number of rainy days is May (18.2 days).
The month with the least rainy days is November (7.5 days).
Average snowfall in September
Basin, MT
- Average snowfall in September: 2.01"
The month with the highest snowfall is February (9.72").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Basin, MT
- Average snowfall days in September: 1.2 days
The month with the highest number of snowfall days is February (18 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Basin, MT
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in September: 9h and 48min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The months with the least sunshine are January and December (Average sunshine: 5h and 36min).
Average sunshine days in September
Basin, MT
- Average sunshine days in September: 17.9 days
The month with the most sunshine days is September (17.9 days).
The month with the least sunshine days is February (8.5 days).
Average UV index in September
Basin, MT
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is February (UV index 1).
Average cloud cover in September
Basin, MT
- Average cloud cover in September: 22
The month with the most cloud cover is February (Cloud cover 48).
The month with the least cloud cover is August (Cloud cover 15).
Average visibility in September
Basin, MT
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February, March and December (5mi).
