December weather forecastGreeley, CO
December
Weather in December
December brings the cold winter in Greeley, Colorado, with the temperatures decreasing substantially. Even though it is a winter month, the lowest temperature remains above freezing at 20.1°F (-6.6°C). The shorter daylight hours and frequent snowfall make it a typical winter month. December greets residents and visitors with a white Christmas, one of the year's most anticipated events. Despite cold weather conditions, the city’s holiday spirit keeps the atmosphere warm and inviting.Temperature
December is the month when Greeley, Colorado, sees the lowest average temperatures, with a high of 38.3°F (3.5°C) and a low of 20.1°F (-6.6°C).Humidity
January and December, with an average relative humidity of 64%, are the most humid months.Rainfall
December is the month with the least rainfall. Rain falls for 1.7 days and accumulates 0.2" (5mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In Greeley, in December, snow falls for 4.5 days, with typically accumulated 1.18" (30mm) of snow. In Greeley, during the entire year, snow falls for 26.6 days and aggregates up to 13.62" (346mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:03 am and sunset at 4:32 pm. On the last day of December, sunrise is at 7:21 am and sunset at 4:42 pm MST.
Sunshine
The months with the least sunshine are February and December, with an average of 6.6h of sunshine.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low health risk from exposure to the Sun's UV radiation for the average person.Note: The maximum UV index of 2 during December translates into these guidelines:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. The midday Sun can be dangerous due to its intense radiation; always find shade and reduce exposure. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Heed this! Snow reflection can almost augment the UV radiation of the sun by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Greeley, CO
- Average high temperature in December: 38.3°F
The warmest month (with the highest average high temperature) is July (89.1°F).
The month with the lowest average high temperature is December (38.3°F).
- Average low temperature in December: 20.1°F
The month with the highest average low temperature is July (62.1°F).
The coldest month (with the lowest average low temperature) is December (20.1°F).
Average pressure in December
Greeley, CO
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in December
Greeley, CO
- Average wind speed in December: 6mph
The windiest month (with the highest average wind speed) is April (8.5mph).
The calmest month (with the lowest average wind speed) is December (6mph).
Average humidity in December
Greeley, CO
- Average humidity in December: 64%
The months with the highest relative humidity are January and December (64%).
The months with the lowest relative humidity are August and September (44%).
Average rainfall in December
Greeley, CO
- Average rainfall in December: 0.2"
The wettest month (with the highest rainfall) is May (1.61").
The driest month (with the least rainfall) is December (0.2").
Average rainfall days in December
Greeley, CO
- Average rainfall days in December: 1.7 days
The month with the highest number of rainy days is July (11.4 days).
The month with the least rainy days is November (1.6 days).
Average snowfall in December
Greeley, CO
- Average snowfall in December: 1.18"
The month with the highest snowfall is February (2.36").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Greeley, CO
- Average snowfall days in December: 4.5 days
The month with the highest number of snowfall days is February (5.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Greeley, CO
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 6h and 36min
The month with the most sunshine is June (Average sunshine: 11h and 54min).
The months with the least sunshine are February and December (Average sunshine: 6h and 36min).
Average sunshine days in December
Greeley, CO
- Average sunshine days in December: 25.9 days
The month with the most sunshine days is December (25.9 days).
The month with the least sunshine days is July (16.7 days).
Average UV index in December
Greeley, CO
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Greeley, CO
- Average cloud cover in December: 27
The month with the most cloud cover is February (Cloud cover 29).
The month with the least cloud cover is June (Cloud cover 16).
Average visibility in December
Greeley, CO
- 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).





