December weather forecastReserve, MT
December
Weather in December
The first month of the winter, December, is still a freezing cold month in Reserve, Montana, with an average temperature fluctuating between 21.9°F (-5.6°C) and 10°F (-12.2°C).Temperature
The shift into December brings a noticeable decrease in the average high-temperature, falling from a wintry 36.3°F (2.4°C) in November to a freezing cold 21.9°F (-5.6°C). During the nights in December, an average low-temperature of 10°F (-12.2°C) is observed.Humidity
In December, the average relative humidity is 87%.Rainfall
In Reserve, in December, during 3.6 rainfall days, 0.51" (13mm) of precipitation is typically accumulated. Throughout the year, there are 93.3 rainfall days, and 12.01" (305mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Reserve, in December, snow falls for 13 days, with typically accumulated 3.19" (81mm) of snow. Throughout the year, there are 66.5 snowfall days, and 19.02" (483mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 8h and 24min of daylight.On the first day of the month, sunrise is at 7:29 am and sunset at 4:04 pm. On the last day of December, sunrise is at 7:50 am and sunset at 4:12 pm MST.
Sunshine
In Reserve, the average sunshine in December is 4.2h.UV index
The average daily maximum UV index in December is 2. A UV Index of 2, and less, symbolizes a low health risk from unprotected exposure to Sun's UV rays for the average person.Note: The maximum UV index, 2 during December, leads to the following recommendations:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. To protect against the Sun's most potent rays, avoid direct exposure around midday. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Be on the lookout! Nearly twofold UV radiation from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Reserve, MT
- Average high temperature in December: 21.9°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is February (19.8°F).
- Average low temperature in December: 10°F
The month with the highest average low temperature is July (61°F).
The coldest month (with the lowest average low temperature) is February (6.3°F).
Average pressure in December
Reserve, MT
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is February (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in December
Reserve, MT
- Average wind speed in December: 9.9mph
The windiest month (with the highest average wind speed) is April (11.1mph).
The calmest month (with the lowest average wind speed) is February (9.2mph).
Average humidity in December
Reserve, MT
- Average humidity in December: 87%
The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is August (46%).
Average rainfall in December
Reserve, MT
- Average rainfall in December: 0.51"
The wettest month (with the highest rainfall) is June (2.17").
The driest month (with the least rainfall) is February (0.47").
Average rainfall days in December
Reserve, MT
- Average rainfall days in December: 3.6 days
The month with the highest number of rainy days is June (13.9 days).
The month with the least rainy days is February (2.6 days).
Average snowfall in December
Reserve, MT
- Average snowfall in December: 3.19"
The month with the highest snowfall is November (3.74").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Reserve, MT
- Average snowfall days in December: 13 days
The month with the highest number of snowfall days is February (13.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Reserve, MT
- Average daylight in December: 8h and 24min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in December: 4h and 12min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 3h and 54min).
Average sunshine days in December
Reserve, MT
- Average sunshine days in December: 17.2 days
The month with the most sunshine days is August (20.1 days).
The months with the least sunshine days are February and June (13.8 days).
Average UV index in December
Reserve, MT
- Average UV index in December: 2
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 December
Reserve, MT
- Average cloud cover in December: 56
The month with the most cloud cover is February (Cloud cover 60).
The months with the least cloud cover are July and August (Cloud cover 19).
Average visibility in December
Reserve, MT
- Average visibility in December: 5mi
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).





