December weather forecastPompeys Pillar, MT
December
Weather in December
The first month of the winter, December, is also a subzero cold month in Pompeys Pillar, Montana, with an average temperature fluctuating between 31.3°F (-0.4°C) and 18.1°F (-7.7°C).Temperature
Temperature records mark December as the coldest month, with highs averaging 31.3°F (-0.4°C) and lows at 18.1°F (-7.7°C).Humidity
In December, the average relative humidity in Pompeys Pillar is 74%.Rainfall
In Pompeys Pillar, Montana, during December, the rain falls for 5.9 days and regularly aggregates up to 0.67" (17mm) of precipitation. Throughout the year, there are 103 rainfall days, and 11.97" (304mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. In Pompeys Pillar, in December, during 10.8 snowfall days, 3.94" (100mm) of snow is typically accumulated. Throughout the year, there are 56.7 snowfall days, and 25.16" (639mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 8h and 42min of daylight.On the first day of December, sunrise is at 7:34 am and sunset at 4:28 pm. On the last day of the month, sunrise is at 7:53 am and sunset at 4:36 pm MST.
Sunshine
In Pompeys Pillar, the average sunshine in December is 5.8h.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low health risk from exposure to the Sun's UV rays for average individuals.Note: The daily high UV index of 2 in December translates into this advice:
Most individuals can handle sun exposure for up to an hour without burning, but children must always be shielded from sun exposure. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades. 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
Pompeys Pillar, MT
- Average high temperature in December: 31.3°F
The warmest month (with the highest average high temperature) is July (87.3°F).
The month with the lowest average high temperature is December (31.3°F).
- Average low temperature in December: 18.1°F
The month with the highest average low temperature is July (62.8°F).
The coldest month (with the lowest average low temperature) is January (17.8°F).
Average pressure in December
Pompeys Pillar, MT
- Average pressure in December: 30.12"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 December
Pompeys Pillar, MT
- Average wind speed in December: 8.2mph
The windiest month (with the highest average wind speed) is April (9.1mph).
The calmest month (with the lowest average wind speed) is July (7.3mph).
Average humidity in December
Pompeys Pillar, MT
- Average humidity in December: 74%
The month with the highest relative humidity is January (78%).
The month with the lowest relative humidity is August (38%).
Average rainfall in December
Pompeys Pillar, MT
- Average rainfall in December: 0.67"
The wettest month (with the highest rainfall) is May (1.81").
The driest month (with the least rainfall) is August (0.63").
Average rainfall days in December
Pompeys Pillar, MT
- Average rainfall days in December: 5.9 days
The month with the highest number of rainy days is May (13.6 days).
The month with the least rainy days is December (5.9 days).
Average snowfall in December
Pompeys Pillar, MT
- Average snowfall in December: 3.94"
The month with the highest snowfall is February (5.43").
The months with the least snowfall are June, July and August (0").
Average snowfall days in December
Pompeys Pillar, MT
- Average snowfall days in December: 10.8 days
The month with the highest number of snowfall days is February (12.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Pompeys Pillar, MT
- Average daylight in December: 8h and 42min
The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).
- Average sunshine in December: 5h and 48min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is February (Average sunshine: 5h and 36min).
Average sunshine days in December
Pompeys Pillar, MT
- Average sunshine days in December: 17.3 days
The month with the most sunshine days is September (21.5 days).
The month with the least sunshine days is February (13.3 days).
Average UV index in December
Pompeys Pillar, MT
- Average UV index in December: 2
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in December
Pompeys Pillar, MT
- Average cloud cover in December: 40
The month with the most cloud cover is February (Cloud cover 43).
The month with the least cloud cover is July (Cloud cover 13).
Average visibility in December
Pompeys Pillar, 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).
