September weather forecastTerry, MT
September
Weather in September
September weather in Terry, Montana marks the onset of autumn. Temperature averages subside from the highs of August, typically embracing milder conditions. First traces of snowfall return for the year, albeit minimal at just 0.47" (12mm). The gradual shift in September's weather scenes the stage for a more pronounced autumn feel come October.Temperature
Terry in September demonstrates a small temperature transition, adjusting from an average high of a moderately hot 83.3°F (28.5°C) in August to an agreeable 73°F (22.8°C). Terry encounters an average low-temperature of 54.5°F (12.5°C) during September nights.Humidity
In Terry, the average relative humidity in September is 46%.Rainfall
In September, the rain falls for 8.3 days. Throughout September, 1.73" (44mm) of precipitation is accumulated. In Terry, during the entire year, the rain falls for 102.6 days and collects up to 13.35" (339mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In Terry, the average length of the day in September is 12h and 32min.On the first day of September, sunrise is at 6:22 am and sunset at 7:39 pm. On the last day of the month, sunrise is at 6:59 am and sunset at 6:42 pm MDT.
Sunshine
In September, the average sunshine is 10.2h.UV index
In Terry, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: A maximum high daily UV index of 4 during September translates into the following directions:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Terry, MT
- Average high temperature in September: 73°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (25.5°F).
- Average low temperature in September: 54.5°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (12.6°F).
Average pressure in September
Terry, MT
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is February (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in September
Terry, MT
- Average wind speed in September: 10.3mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is August (9.3mph).
Average humidity in September
Terry, MT
- Average humidity in September: 46%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is August (43%).
Average rainfall in September
Terry, MT
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is May (2.2").
The driest month (with the least rainfall) is January (0.51").
Average rainfall days in September
Terry, MT
- Average rainfall days in September: 8.3 days
The month with the highest number of rainy days is May (13.7 days).
The month with the least rainy days is February (4 days).
Average snowfall in September
Terry, MT
- Average snowfall in September: 0"
The month with the highest snowfall is February (3.62").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Terry, MT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.9 days).
The months with the least snowfall days are July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Terry, MT
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in September: 10h and 12min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The months with the least sunshine are February and December (Average sunshine: 4h and 54min).
Average sunshine days in September
Terry, MT
- Average sunshine days in September: 19.8 days
The month with the most sunshine days is September (19.8 days).
The month with the least sunshine days is June (13.1 days).
Average UV index in September
Terry, MT
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are November and December (UV index 1).
Average cloud cover in September
Terry, MT
- Average cloud cover in September: 22
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
Terry, 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).
