September weather forecastZortman, MT
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Zortman, Montana, with an average temperature fluctuating between 53.4°F (11.9°C) and 70.9°F (21.6°C).Temperature
The shift to September brings a decrease in the average high-temperature, falling from a warm 82.2°F (27.9°C) in August to a pleasant 70.9°F (21.6°C). The average low-temperature, in September, is a cool 53.4°F (11.9°C).Humidity
The average relative humidity in September is 46%.Rainfall
In Zortman, during September, the rain falls for 8.7 days and regularly aggregates up to 1.1" (28mm) of precipitation. In Zortman, during the entire year, the rain falls for 103.3 days and collects up to 11.81" (300mm) of precipitation.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.2" (5mm) of snow. Throughout the year, there are 59.6 snowfall days, and 20.28" (515mm) of snow is accumulated.Daylight
In Zortman, the average length of the day in September is 12h and 33min.On the first day of September, sunrise is at 6:33 am and sunset at 7:54 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 6:54 pm MDT.
Sunshine
In September, the average sunshine is 9.9h.UV index
In Zortman, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the average person.Note: The maximum daily UV index of 4 in September interprets into the following recommendations:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun is most powerful around mid-day, so it's a good practice to reduce direct exposure. Opt for tightly woven and loose clothing to enhance protection from the Sun. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Zortman, MT
- Average high temperature in September: 70.9°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The months with the lowest average high temperature are January and February (25.7°F).
- Average low temperature in September: 53.4°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (11.8°F).
Average pressure in September
Zortman, MT
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is February (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in September
Zortman, MT
- Average wind speed in September: 9.9mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is February (8.8mph).
Average humidity in September
Zortman, MT
- Average humidity in September: 46%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (41%).
Average rainfall in September
Zortman, MT
- Average rainfall in September: 1.1"
The wettest months (with the highest rainfall) are May and June (1.89").
The driest months (with the least rainfall) are February and December (0.55").
Average rainfall days in September
Zortman, MT
- Average rainfall days in September: 8.7 days
The month with the highest number of rainy days is May (14.1 days).
The month with the least rainy days is December (4 days).
Average snowfall in September
Zortman, MT
- Average snowfall in September: 0.2"
The month with the highest snowfall is December (3.9").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Zortman, MT
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (12.7 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Zortman, 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 30min).
- Average sunshine in September: 9h and 54min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Zortman, MT
- Average sunshine days in September: 19.6 days
The month with the most sunshine days is September (19.6 days).
The month with the least sunshine days is April (13.4 days).
Average UV index in September
Zortman, MT
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Zortman, MT
- Average cloud cover in September: 24
The month with the most cloud cover is February (Cloud cover 49).
The months with the least cloud cover are July and August (Cloud cover 17).
Average visibility in September
Zortman, MT
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).





