Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December's arrival brings a noticeable temperature shift, dropping from a cold 39.4°F (4.1°C) in November to a subzero cold 24.6°F (-4.1°C). During December, Sidney's temperature falls to a steady low-temperature average of 12.7°F (-10.7°C).Humidity
In December, the average relative humidity is 84%.Rainfall
In Sidney, during December, the rain falls for 3.5 days and regularly aggregates up to 0.31" (8mm) of precipitation. In Sidney, during the entire year, the rain falls for 85.7 days and collects up to 8.5" (216mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Sidney, during December, snow falls for 11.2 days and regularly aggregates up to 1.65" (42mm) of snow. In Sidney, during the entire year, snow falls for 56.1 days and aggregates up to 8.94" (227mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 30min of daylight.On the first day of the month, sunrise is at 7:25 am and sunset at 4:06 pm. On the last day of December, sunrise is at 7:45 am and sunset at 4:14 pm MST.
Sunshine
The average sunshine in December is 4.5h.UV index
In December, the average daily maximum UV index in Sidney is 2. A UV Index value of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for the ordinary person.Note: In December, the maximum UV index of 2 translates into these guidelines:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December in Sidney?
What is the average humidity in December?
How much does it rain in December?
How much does it snow in December?
What is the month with the shortest days in Sidney?
How many hours of daylight does Sidney have in December?
What time are sunrise and sunset in December?
How long on average sun shines in December?
How high is the UV index in December?
Average temperature in December
Sidney, MT
- Average high temperature in December: 24.6°F
The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (23.4°F).
- Average low temperature in December: 12.7°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (9.9°F).
Average pressure in December
Sidney, MT
- Average pressure in December: 30.14"Hg
The month with the highest atmospheric pressure is February (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in December
Sidney, MT
- Average wind speed in December: 10mph
The windiest months (with the highest average wind speed) are April and October (11.1mph).
The calmest month (with the lowest average wind speed) is February (9.2mph).
Average humidity in December
Sidney, MT
- Average humidity in December: 84%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is August (45%).
Average rainfall in December
Sidney, MT
- Average rainfall in December: 0.31"
The wettest month (with the highest rainfall) is July (1.34").
The driest month (with the least rainfall) is January (0.24").
Average rainfall days in December
Sidney, MT
- Average rainfall days in December: 3.5 days
The month with the highest number of rainy days is June (11.4 days).
The months with the least rainy days are January and February (3.2 days).
Average snowfall in December
Sidney, MT
- Average snowfall in December: 1.65"
The month with the highest snowfall is February (1.77").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Sidney, MT
- Average snowfall days in December: 11.2 days
The month with the highest number of snowfall days is February (12 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Sidney, MT
- Average daylight in December: 8h and 3min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in December: 4h and 3min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 18min).
Average sunshine days in December
Sidney, MT
- Average sunshine days in December: 18.7 days
The month with the most sunshine days is September (20.7 days).
The month with the least sunshine days is April (15.8 days).
Average UV index in December
Sidney, 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 and February (UV index 1).
Average cloud cover in December
Sidney, MT
- Average cloud cover in December: 53
The month with the most cloud cover is February (Cloud cover 54).
The month with the least cloud cover is July (Cloud cover 18).
Average visibility in December
Sidney, 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).
Sidney, Montana, USA
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