December weather forecastRockyford, SD
December
Weather in December
The first month of the winter, December, is still a cold month in Rockyford, South Dakota, with an average temperature fluctuating between 32.4°F (0.2°C) and 18.7°F (-7.4°C).Temperature
Rockyford's December weather, marked by an average high temperature of 32.4°F (0.2°C) and an average low temperature of 18.7°F (-7.4°C), is the coldest in the year.Humidity
In December, the average relative humidity is 76%.Rainfall
In December, the rain falls for 2.5 days. Throughout December, 0.87" (22mm) of precipitation is accumulated. In Rockyford, during the entire year, the rain falls for 86.7 days and collects up to 13.66" (347mm) of precipitation.Snowfall
Months with snowfall are January through May, September through December. In Rockyford, during December, snow falls for 8.2 days and regularly aggregates up to 3.9" (99mm) of snow. Throughout the year, there are 47.4 snowfall days, and 22.72" (577mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 0min of daylight.On the first day of December, sunrise is at 7:03 am and sunset at 4:14 pm. On the last day of the month, sunrise is at 7:22 am and sunset at 4:23 pm MST.
Sunshine
In December, the average sunshine is 5.7h.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 unprotected exposure to Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 2 in December converts into the following recommendations:
Protection from prolonged sun exposure is necessary for babies, children, and individuals with sensitive skin. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rockyford, SD
- Average high temperature in December: 32.4°F
The warmest month (with the highest average high temperature) is July (87.6°F).
The month with the lowest average high temperature is December (32.4°F).
- Average low temperature in December: 18.7°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (18.1°F).
Average pressure in December
Rockyford, SD
- 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 (29.85"Hg).
Average wind speed in December
Rockyford, SD
- Average wind speed in December: 10.4mph
The windiest month (with the highest average wind speed) is April (12.2mph).
The calmest month (with the lowest average wind speed) is August (10.2mph).
Average humidity in December
Rockyford, SD
- Average humidity in December: 76%
The month with the highest relative humidity is January (80%).
The month with the lowest relative humidity is August (48%).
Average rainfall in December
Rockyford, SD
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is May (2.13").
The driest month (with the least rainfall) is January (0.55").
Average rainfall days in December
Rockyford, SD
- Average rainfall days in December: 2.5 days
The month with the highest number of rainy days is May (13.1 days).
The months with the least rainy days are February and December (2.5 days).
Average snowfall in December
Rockyford, SD
- Average snowfall in December: 3.9"
The month with the highest snowfall is February (4.02").
The months with the least snowfall are June, July and August (0").
Average snowfall days in December
Rockyford, SD
- Average snowfall days in December: 8.2 days
The month with the highest number of snowfall days is February (11.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Rockyford, SD
- Average daylight in December: 9h and 0min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in December: 5h and 42min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 12min).
Average sunshine days in December
Rockyford, SD
- Average sunshine days in December: 20.8 days
The month with the most sunshine days is September (22.8 days).
The month with the least sunshine days is April (13.2 days).
Average UV index in December
Rockyford, SD
- 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, February, November and December (UV index 2).
Average cloud cover in December
Rockyford, SD
- Average cloud cover in December: 39
The month with the most cloud cover is February (Cloud cover 44).
The month with the least cloud cover is August (Cloud cover 16).
Average visibility in December
Rockyford, SD
- 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).
