December weather forecastFort Thompson, SD
December
Weather in December
December, the first month of the winter in Fort Thompson, is still a freezing cold month, with an average temperature varying between 16.9°F (-8.4°C) and 29.1°F (-1.6°C).Temperature
The onset of December brings a clear temperature shift, with the average high-temperature decreasing from a frosty 45.5°F (7.5°C) in November to a freezing cold 29.1°F (-1.6°C). The average low-temperature, in December, is a still subzero cold 16.9°F (-8.4°C).Humidity
In Fort Thompson, the average relative humidity in December is 82%.Rainfall
In December, in Fort Thompson, the rain falls for 3.9 days. Throughout December, 0.94" (24mm) of precipitation is accumulated. Throughout the year, there are 107.6 rainfall days, and 17.83" (453mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, October through December. In December, it is snowing for 9.6 days. Throughout December, 3.07" (78mm) of snow is accumulated. Throughout the year, there are 50.9 snowfall days, and 17.87" (454mm) of snow is accumulated.Daylight
With an average of 8h and 54min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:53 am and sunset at 5:00 pm. On the last day of December, sunrise is at 8:12 am and sunset at 5:09 pm CST.
Sunshine
The average sunshine in December is 4.9h.UV index
In Fort Thompson, the average daily maximum UV index in December is 2. A UV Index estimate of 2, and below, represents a low threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: The daily maximum UV index of 2 in December interprets into the following advice:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Take to heart! Snow reflection can almost magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Fort Thompson, SD
- Average high temperature in December: 29.1°F
The warmest month (with the highest average high temperature) is July (88°F).
The month with the lowest average high temperature is January (26.1°F).
- Average low temperature in December: 16.9°F
The month with the highest average low temperature is July (66.2°F).
The coldest month (with the lowest average low temperature) is January (12.6°F).
Average pressure in December
Fort Thompson, SD
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).
Average wind speed in December
Fort Thompson, SD
- Average wind speed in December: 10mph
The windiest month (with the highest average wind speed) is April (11.3mph).
The calmest month (with the lowest average wind speed) is August (9.1mph).
Average humidity in December
Fort Thompson, SD
- Average humidity in December: 82%
The month with the highest relative humidity is January (86%).
The month with the lowest relative humidity is September (58%).
Average rainfall in December
Fort Thompson, SD
- Average rainfall in December: 0.94"
The wettest month (with the highest rainfall) is June (3.03").
The driest month (with the least rainfall) is November (0.55").
Average rainfall days in December
Fort Thompson, SD
- Average rainfall days in December: 3.9 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is February (3.3 days).
Average snowfall in December
Fort Thompson, SD
- Average snowfall in December: 3.07"
The month with the highest snowfall is February (3.66").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Fort Thompson, SD
- Average snowfall days in December: 9.6 days
The months with the highest number of snowfall days are January and February (11.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Fort Thompson, SD
- Average daylight in December: 8h and 54min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in December: 4h and 54min
The month with the most sunshine is July (Average sunshine: 11h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in December
Fort Thompson, SD
- Average sunshine days in December: 19.5 days
The month with the most sunshine days is November (20.7 days).
The month with the least sunshine days is April (11.8 days).
Average UV index in December
Fort Thompson, SD
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is February (UV index 1).
Average cloud cover in December
Fort Thompson, SD
- Average cloud cover in December: 47
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 20).
Average visibility in December
Fort Thompson, SD
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
