December weather forecastGillette, WY
December
Weather in December
December heralds the arrival of the holiday season, painting Gillette in festive hues with an added layer of frost. The average high settles at a cool 29.7°F (-1.3°C), well within the margins that define a cold month. Uniform visibility across the month ensures clear skies for stargazers and astronomy enthusiasts despite decreased daylight hours. Snowfall, akin to an annual tradition, gracefully blankets the city towards the end of the month. December rounds off the year embodying the charm of a winter wonderland embracing a frosty white Christmas and year-end celebrations.Temperature
December, on average, is the coldest month, registering a high temperature of 29.7°F (-1.3°C) and a low of 17.2°F (-8.2°C).Humidity
In December, the average relative humidity in Gillette is 75%.Rainfall
In December, the rain falls for 1.8 days. Throughout December, 0.43" (11mm) of precipitation is accumulated. Throughout the year, in Gillette, there are 108.9 rainfall days, and 15.59" (396mm) of precipitation is accumulated.Snowfall
Months with snowfall in Gillette are January through May, September through December. In Gillette, during December, snow falls for 6.2 days and regularly aggregates up to 1.81" (46mm) of snow. Throughout the year, there are 50.5 snowfall days, and 19.53" (496mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 8h and 54min of daylight.On the first day of the month, sunrise is at 7:18 am and sunset at 4:24 pm. On the last day of December, sunrise is at 7:37 am and sunset at 4:33 pm MST.
Sunshine
In December, the average sunshine is 5.9h.UV index
January, February, April, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Gillette. A UV Index estimate of 2, and below, represents a minimal health hazard from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The average daily UV index of 2 in December transforms into the following instructions:
Although prolonged sun exposure does not typically bother most people, children, babies, and those with sensitive skin should always have protection. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage. Forewarned is forearmed! The Sun's UV radiation can be almost doubled in intensity by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Gillette, WY
- Average high temperature in December: 29.7°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is December (29.7°F).
- Average low temperature in December: 17.2°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is February (16.7°F).
Average pressure in December
Gillette, WY
- 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 (29.84"Hg).
Average wind speed in December
Gillette, WY
- Average wind speed in December: 11mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest months (with the lowest average wind speed) are July and August (9.1mph).
Average humidity in December
Gillette, WY
- Average humidity in December: 75%
The month with the highest relative humidity is January (78%).
The month with the lowest relative humidity is August (41%).
Average rainfall in December
Gillette, WY
- Average rainfall in December: 0.43"
The wettest month (with the highest rainfall) is May (3.11").
The driest month (with the least rainfall) is January (0.39").
Average rainfall days in December
Gillette, WY
- Average rainfall days in December: 1.8 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is February (1.5 days).
Average snowfall in December
Gillette, WY
- Average snowfall in December: 1.81"
The month with the highest snowfall is April (3.82").
The months with the least snowfall are June, July and August (0").
Average snowfall days in December
Gillette, WY
- Average snowfall days in December: 6.2 days
The month with the highest number of snowfall days is February (9.1 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in December /
Average sunshine in December
Gillette, WY
- 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: 5h and 54min
The months with the most sunshine are July and August (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 36min).
Average sunshine days in December
Gillette, WY
- Average sunshine days in December: 22.4 days
The month with the most sunshine days is December (22.4 days).
The month with the least sunshine days is May (9.3 days).
Average UV index in December
Gillette, WY
- 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, April, November and December (UV index 2).
Average cloud cover in December
Gillette, WY
- Average cloud cover in December: 39
The month with the most cloud cover is February (Cloud cover 43).
The month with the least cloud cover is August (Cloud cover 16).
Average visibility in December
Gillette, WY
- 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).
