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
The start of December brings a distinct shift in the average high-temperature, dropping from November's chilly 42.8°F (6°C) to a freezing cold 28.2°F (-2.1°C). In December, the nighttime temperature lowers to an average of 17.8°F (-7.9°C).Humidity
The average relative humidity in December is 86%.Rainfall
In Duncan, Iowa, in December, during 5.5 rainfall days, 1.3" (33mm) of precipitation is typically accumulated. In Duncan, Iowa, during the entire year, the rain falls for 127.1 days and collects up to 24.8" (630mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In Duncan, during December, snow falls for 11.2 days and regularly aggregates up to 3.19" (81mm) of snow. Throughout the year, there are 51.2 snowfall days, and 20.91" (531mm) of snow is accumulated.Daylight
The month with the shortest days in Duncan is December, with an average of 9h and 6min of daylight.On the first day of December, sunrise is at 7:27 am and sunset at 4:40 pm. On the last day of the month, sunrise is at 7:46 am and sunset at 4:49 pm CST.
Sunshine
In December, the average sunshine is 4.2h.UV index
January and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a low health risk from exposure to the Sun's UV radiation for the ordinary person.Note: A daily high UV index of 1 in December leads to these guidelines:
Prolonged exposure to sunlight rarely troubles the majority, but constant protection is vital for babies, children, and fair-skinned people. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear. Be prepared! The intensity of the Sun's UV radiation can be amplified nearly double due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in Duncan in December?
What is the average humidity in December?
How many days does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
What time are sunrise and sunset in December?
How many hours of sunshine does Duncan have in December?
What is the month with the lowest UV index?
How high is the UV index in December?
Average temperature in December
Duncan, IA
- Average high temperature in December: 28.2°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (22.8°F).
- Average low temperature in December: 17.8°F
The month with the highest average low temperature is July (63°F).
The coldest month (with the lowest average low temperature) is January (10.4°F).
Average pressure in December
Duncan, IA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in December
Duncan, IA
- Average wind speed in December: 10.3mph
The windiest month (with the highest average wind speed) is April (11mph).
The calmest month (with the lowest average wind speed) is July (7.4mph).
Average humidity in December
Duncan, IA
- Average humidity in December: 86%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is October (69%).
Average rainfall in December
Duncan, IA
- Average rainfall in December: 1.3"
The wettest month (with the highest rainfall) is June (3.82").
The driest month (with the least rainfall) is January (0.94").
Average rainfall days in December
Duncan, IA
- Average rainfall days in December: 5.5 days
The month with the highest number of rainy days is June (17.8 days).
The month with the least rainy days is February (2.8 days).
Average snowfall in December
Duncan, IA
- Average snowfall in December: 3.19"
The month with the highest snowfall is February (5.71").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Duncan, IA
- Average snowfall days in December: 11.2 days
The month with the highest number of snowfall days is January (13.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Duncan, IA
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 1min
The month with the most sunshine is July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Duncan, IA
- Average sunshine days in December: 16.6 days
The month with the most sunshine days is November (18.3 days).
The month with the least sunshine days is June (10.4 days).
Average UV index in December
Duncan, IA
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Duncan, IA
- Average cloud cover in December: 58
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility in December
Duncan, IA
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January and July (5mi).
Duncan, Iowa, USA
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