December weather forecastWest Yellowstone, MT
December
Weather in December
Ending the year with a high temperature averaging 20.1°F (-6.6°C), December plunges West Yellowstone, Montana into the midst of winter. With snowfall, comes the onset of the holiday season, transforming the town into a picturesque postcard scenario. Skiers and snowboarders take over the mountains, making the most of the heavy winter snow. The magic of the holiday season is magnified by the cold weather, capping off the year in a perfect wintery glow.Temperature
December is the month that records the lowest temperatures, with averages ranging from a high of 20.1°F (-6.6°C) to a low of 4.8°F (-15.1°C).Humidity
In December, the average relative humidity is 93%.Rainfall
In West Yellowstone, during December, the rain falls for 4 days and regularly aggregates up to 1.97" (50mm) of precipitation. In West Yellowstone, Montana, during the entire year, the rain falls for 109.2 days and collects up to 23.15" (588mm) of precipitation.Snowfall
Months with snowfall in West Yellowstone are January through July, September through December. In West Yellowstone, in December, during 23.5 snowfall days, 16.38" (416mm) of snow is typically accumulated. In West Yellowstone, during the entire year, snow falls for 159.3 days and aggregates up to 120.47" (3060mm) of snow.Daylight
December has the shortest days of the year, with an average of 8h and 54min of daylight.On the first day of the month, sunrise is at 7:42 am and sunset at 4:45 pm. On the last day of December, sunrise is at 8:01 am and sunset at 4:54 pm MST.
Sunshine
The months with the least sunshine in West Yellowstone are January, February and December, with an average of 3.3h of sunshine.UV index
The months with the lowest UV index are January through April, October through December, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a low health risk from exposure to the Sun's UV radiation for average individuals.Note: The UV index of 1 during December translates into the following guidance:
Prolonged sun exposure should always be prevented in babies, children, and those with sensitive skin. Midday Sun has the strongest UV rays, making it crucial to limit exposure and find shade. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
West Yellowstone, MT
- Average high temperature in December: 20.1°F
The warmest month (with the highest average high temperature) is July (72.9°F).
The month with the lowest average high temperature is December (20.1°F).
- Average low temperature in December: 4.8°F
The month with the highest average low temperature is August (43.7°F).
The coldest month (with the lowest average low temperature) is December (4.8°F).
Average pressure in December
West Yellowstone, MT
- Average pressure in December: 30.23"Hg
The month with the highest atmospheric pressure is January (30.24"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
West Yellowstone, MT
- Average wind speed in December: 6.2mph
The windiest month (with the highest average wind speed) is June (6.8mph).
The calmest month (with the lowest average wind speed) is August (5.8mph).
Average humidity in December
West Yellowstone, MT
- Average humidity in December: 93%
The month with the highest relative humidity is February (95%).
The month with the lowest relative humidity is August (50%).
Average rainfall in December
West Yellowstone, MT
- Average rainfall in December: 1.97"
The wettest month (with the highest rainfall) is May (2.8").
The driest month (with the least rainfall) is July (0.91").
Average rainfall days in December
West Yellowstone, MT
- Average rainfall days in December: 4 days
The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (2.2 days).
Average snowfall in December
West Yellowstone, MT
- Average snowfall in December: 16.38"
The month with the highest snowfall is February (17.83").
The month with the least snowfall is August (0").
Average snowfall days in December
West Yellowstone, MT
- Average snowfall days in December: 23.5 days
The month with the highest number of snowfall days is March (24.4 days).
The months with the least snowfall days are July and August (0.2 days).
Average daylight in December /
Average sunshine in December
West Yellowstone, MT
- Average daylight in December: 8h and 54min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in December: 3h and 18min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The months with the least sunshine are January, February and December (Average sunshine: 3h and 18min).
Average sunshine days in December
West Yellowstone, MT
- Average sunshine days in December: 8.2 days
The months with the most sunshine days are July and September (14.7 days).
The month with the least sunshine days is February (5.3 days).
Average UV index in December
West Yellowstone, MT
- Average UV index in December: 1
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 1).
Average cloud cover in December
West Yellowstone, MT
- Average cloud cover in December: 72
The month with the most cloud cover is February (Cloud cover 76).
The month with the least cloud cover is July (Cloud cover 16).
Average visibility in December
West Yellowstone, MT
- Average visibility in December: 3mi
The months with the highest visibility are June, July, August and September (6mi).
The months with the lowest visibility are January, February, March and December (3mi).
