September weather forecastBig Sandy, MT
September
Weather in September
September, the first month of the autumn in Big Sandy, is still a pleasant month, with an average temperature fluctuating between 71.4°F (21.9°C) and 52.9°F (11.6°C).Temperature
The arrival of September corresponds with a shift in temperature, down from a warm 82.6°F (28.1°C) in August to an agreeable 71.4°F (21.9°C). Big Sandy records a mean low-temperature of 52.9°F (11.6°C) in September.Humidity
The average relative humidity in September is 44%.Rainfall
In Big Sandy, Montana, in September, it is raining for 6.6 days, with typically 0.47" (12mm) of accumulated precipitation. Throughout the year, there are 91 rainfall days, and 6.42" (163mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows in Big Sandy. Throughout September, in the average 0.5 snowfall days, it receives 0.43" (11mm) of snow. In Big Sandy, during the entire year, snow falls for 44.2 days and aggregates up to 11.18" (284mm) of snow.Daylight
In September, the average length of the day is 12h and 34min.On the first day of September, sunrise is at 6:39 am and sunset at 8:00 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 7:00 pm MDT.
Sunshine
In Big Sandy, the average sunshine in September is 9.9h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Enhance your sun protection with tightly woven, yet airy clothing. Be informed! The Sun's UV radiation can be nearly doubled due to the reflection from snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Big Sandy, MT
- Average high temperature in September: 71.4°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is December (30.2°F).
- Average low temperature in September: 52.9°F
The month with the highest average low temperature is August (61.3°F).
The coldest month (with the lowest average low temperature) is February (17.8°F).
Average pressure in September
Big Sandy, MT
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Big Sandy, MT
- Average wind speed in September: 9.1mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is August (8.5mph).
Average humidity in September
Big Sandy, MT
- Average humidity in September: 44%
The month with the highest relative humidity is January (79%).
The month with the lowest relative humidity is August (38%).
Average rainfall in September
Big Sandy, MT
- Average rainfall in September: 0.47"
The wettest month (with the highest rainfall) is June (1.22").
The driest month (with the least rainfall) is December (0.28").
Average rainfall days in September
Big Sandy, MT
- Average rainfall days in September: 6.6 days
The month with the highest number of rainy days is May (12.5 days).
The month with the least rainy days is February (4.2 days).
Average snowfall in September
Big Sandy, MT
- Average snowfall in September: 0.43"
The month with the highest snowfall is January (2.4").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Big Sandy, MT
- Average snowfall days in September: 0.5 days
The month with the highest number of snowfall days is January (9.2 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Big Sandy, 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 54min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is February (Average sunshine: 5h and 18min).
Average sunshine days in September
Big Sandy, MT
- Average sunshine days in September: 21.5 days
The month with the most sunshine days is September (21.5 days).
The month with the least sunshine days is June (14.6 days).
Average UV index in September
Big Sandy, MT
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Big Sandy, 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 14).
Average visibility in September
Big Sandy, 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).
