December weather forecastTerry, MT
December
Weather in December
Winter's peak is evident in the December weather in Terry, Montana. A clear drop in temperature from November characterizes December as a quintessential winter month. A high of 2.95" (75mm) of snow over 11.5 days reinforces the cold-dominated narratives. December's weather conditions go full circle, establishing a cold trend that will see the New Year into January.Temperature
The shift from November to December corresponds with a decrease in the average high-temperature, down to a subzero cold 26.2°F (-3.2°C) from an icy 40.5°F (4.7°C). Throughout the month of December, Terry witnesses an average low-temperature of 14.2°F (-9.9°C).Humidity
In December, the average relative humidity is 82%.Rainfall
In Terry, in December, it is raining for 4.1 days, with typically 0.59" (15mm) of accumulated precipitation. In Terry, during the entire year, the rain falls for 102.6 days and collects up to 13.35" (339mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In Terry, in December, snow falls for 11.5 days, with typically accumulated 2.95" (75mm) of snow. Throughout the year, there are 58.7 snowfall days, and 17.28" (439mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 8h and 36min of daylight.On the first day of the month, sunrise is at 7:26 am and sunset at 4:14 pm. On the last day of December, sunrise is at 7:46 am and sunset at 4:23 pm MST.
Sunshine
February and December, with an average of 4.9h of sunshine, are months with the least sunshine.UV index
November and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV rays for average individuals.Note: A daily high UV index of 1 in December leads to these guidelines:
Protection from prolonged sun exposure is necessary for babies, children, and individuals with sensitive skin. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses. Keep in mind! Snow's reflective quality 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 December
Terry, MT
- Average high temperature in December: 26.2°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 December: 14.2°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 December
Terry, MT
- Average pressure in December: 30.14"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 December
Terry, MT
- Average wind speed in December: 10.2mph
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 December
Terry, MT
- Average humidity in December: 82%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is August (43%).
Average rainfall in December
Terry, MT
- Average rainfall in December: 0.59"
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 December
Terry, MT
- Average rainfall days in December: 4.1 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 December
Terry, MT
- Average snowfall in December: 2.95"
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 December
Terry, MT
- Average snowfall days in December: 11.5 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 December /
Average sunshine in December
Terry, MT
- Average daylight in December: 8h and 36min
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 December: 4h and 54min
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 December
Terry, MT
- Average sunshine days in December: 17.5 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 December
Terry, MT
- Average UV index in December: 1
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 December
Terry, MT
- Average cloud cover in December: 48
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 December
Terry, MT
- Average visibility in December: 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).





