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
As Chelsea transitions into December, the average high-temperature shows a marked reduction, decreasing from an icy 41.7°F (5.4°C) in November to a freezing cold 25°F (-3.9°C). Chelsea registers a consistent average low-temperature of 12.7°F (-10.7°C) during December.Humidity
The average relative humidity in December is 85%.Rainfall
In Chelsea, in December, it is raining for 3.1 days, with typically 0.87" (22mm) of accumulated precipitation. In Chelsea, during the entire year, the rain falls for 97.2 days and collects up to 18.35" (466mm) of precipitation.Snowfall
Months with snowfall in Chelsea are January through May, October through December. In Chelsea, South Dakota, in December, snow falls for 11.4 days, with typically accumulated 3.43" (87mm) of snow. In Chelsea, during the entire year, snow falls for 54.8 days and aggregates up to 19.13" (486mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 48min of daylight.On the first day of December, sunrise is at 7:54 am and sunset at 4:54 pm. On the last day of the month, sunrise is at 8:13 am and sunset at 5:02 pm CST.
Sunshine
In December, the average sunshine is 4.3h.UV index
In December, the average daily maximum UV index in Chelsea is 2. A UV Index reading of 2, and below, represents a low threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: An average maximum UV index of 2 in December leads to these recommendations:
Despite the majority tolerating prolonged sun exposure, those with sensitive skin, infants, and children demand continual protection. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. During bright days, sunglasses that offer UVA and UVB defense are recommended. Keep in mind! Snow's reflective quality 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 Chelsea?
What is the average humidity in December in Chelsea?
How many days does it rain in December in Chelsea?
How much does it snow in Chelsea in December?
What is the month with the shortest days in Chelsea?
What is the average length of the day in December in Chelsea?
When are sunrise and sunset in December in Chelsea?
How long on average sun shines in December in Chelsea?
How high is the UV index in December in Chelsea?
Average temperature in December
Chelsea, SD
- Average high temperature in December: 25°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (20.7°F).
- Average low temperature in December: 12.7°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (6.3°F).
Average pressure in December
Chelsea, SD
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is February (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in December
Chelsea, SD
- Average wind speed in December: 9.5mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (8.3mph).
Average humidity in December
Chelsea, SD
- Average humidity in December: 85%
The month with the highest relative humidity is January (88%).
The months with the lowest relative humidity are August and September (60%).
Average rainfall in December
Chelsea, SD
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is June (3.46").
The driest month (with the least rainfall) is January (0.59").
Average rainfall days in December
Chelsea, SD
- Average rainfall days in December: 3.1 days
The month with the highest number of rainy days is June (15 days).
The month with the least rainy days is February (2 days).
Average snowfall in December
Chelsea, SD
- Average snowfall in December: 3.43"
The month with the highest snowfall is January (3.82").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Chelsea, SD
- Average snowfall days in December: 11.4 days
The month with the highest number of snowfall days is January (13 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Chelsea, SD
- Average daylight in December: 8h and 5min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in December: 4h and 2min
The month with the most sunshine is July (Average sunshine: 11h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in December
Chelsea, SD
- Average sunshine days in December: 18.9 days
The month with the most sunshine days is November (20.9 days).
The month with the least sunshine days is June (12.7 days).
Average UV index in December
Chelsea, SD
- 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 and November (UV index 1).
Average cloud cover in December
Chelsea, SD
- Average cloud cover in December: 54
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are July and August (Cloud cover 23).
Average visibility in December
Chelsea, 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).
Chelsea, South Dakota, USA
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