December weather forecastGreen River, WY
December
Weather in December
Winter takes a firm hold in Green River, Wyoming, during December. Temperatures continue their downward trend since November, with average lows of 11.5°F (-11.4°C), coldest for the year, and highs at 25.7°F (-3.5°C). An additional increase in snowfall underpins the grip of winter, as shifts in the frequented weather pattern signify the city's complete move into the cold season. Days become shorter as the daylight hours decrease to their yearly low, further amplifying the winter chill. Hence, December is quintessentially winter-centric, characterised by freezing cold temperatures, regular snowfall and a stark contrast to the otherwise warmer months.Temperature
December, with its high-temperature average of 25.7°F (-3.5°C) and a low-temperature average of 11.5°F (-11.4°C), is the coldest month.Humidity
In December, the average relative humidity is 82%.Rainfall
In Green River, in December, during 4.7 rainfall days, 0.71" (18mm) of precipitation is typically accumulated. Throughout the year, there are 93.5 rainfall days, and 10.31" (262mm) of precipitation is accumulated.Snowfall
January through June, September through December are months with snowfall. In Green River, in December, during 13.5 snowfall days, 4.37" (111mm) of snow is typically accumulated. Throughout the year, there are 75.5 snowfall days, and 30.16" (766mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:25 am and sunset at 4:48 pm. On the last day of the month, sunrise is at 7:44 am and sunset at 4:58 pm MST.
Sunshine
The months with the least sunshine are January and December, with an average of 5.9h 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 2. A UV Index value of 2, and less, symbolizes a minimal health hazard from unsafe exposure to UV radiation for average individuals.Note: In December, the maximum UV index of 2 suggests these recommendations:
Unlike children, who always need sun protection, most individuals can remain in the sun for up to an hour without getting burnt. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Green River, WY
- Average high temperature in December: 25.7°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is December (25.7°F).
- Average low temperature in December: 11.5°F
The month with the highest average low temperature is July (60.4°F).
The coldest month (with the lowest average low temperature) is January (10.8°F).
Average pressure in December
Green River, WY
- Average pressure in December: 30.24"Hg
The month with the highest atmospheric pressure is January (30.28"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in December
Green River, WY
- Average wind speed in December: 9.3mph
The windiest month (with the highest average wind speed) is April (12.2mph).
The calmest month (with the lowest average wind speed) is August (8.7mph).
Average humidity in December
Green River, WY
- Average humidity in December: 82%
The month with the highest relative humidity is January (84%).
The months with the lowest relative humidity are July and August (31%).
Average rainfall in December
Green River, WY
- Average rainfall in December: 0.71"
The wettest month (with the highest rainfall) is May (1.5").
The driest month (with the least rainfall) is July (0.47").
Average rainfall days in December
Green River, WY
- Average rainfall days in December: 4.7 days
The month with the highest number of rainy days is May (13.8 days).
The month with the least rainy days is December (4.7 days).
Average snowfall in December
Green River, WY
- Average snowfall in December: 4.37"
The month with the highest snowfall is March (6.14").
The months with the least snowfall are July and August (0").
Average snowfall days in December
Green River, WY
- Average snowfall days in December: 13.5 days
The month with the highest number of snowfall days is December (13.5 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in December /
Average sunshine in December
Green River, WY
- Average daylight in December: 9h and 12min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 5h and 54min
The months with the most sunshine are July and August (Average sunshine: 11h and 48min).
The months with the least sunshine are January and December (Average sunshine: 5h and 54min).
Average sunshine days in December
Green River, WY
- Average sunshine days in December: 16.4 days
The month with the most sunshine days is September (19.8 days).
The month with the least sunshine days is April (11.5 days).
Average UV index in December
Green River, WY
- Average UV index in December: 2
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover in December
Green River, WY
- Average cloud cover in December: 41
The month with the most cloud cover is February (Cloud cover 43).
The month with the least cloud cover is August (Cloud cover 13).
Average visibility in December
Green River, WY
- Average visibility in December: 5mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (5mi).
