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
Onset of December witnesses a reduction in the average high-temperature, falling from a frosty 43°F (6.1°C) in November to a subzero cold 29.8°F (-1.2°C). December nights in Sumner cool down to an average low-temperature of 19.4°F (-7°C).Humidity
The average relative humidity in December is 84%.Rainfall
In Sumner, during December, the rain falls for 6.4 days and regularly aggregates up to 1.61" (41mm) of precipitation. In Sumner, during the entire year, the rain falls for 146.8 days and collects up to 30.79" (782mm) of precipitation.Snowfall
Months with snowfall in Sumner, Iowa, are January through May, October through December. In Sumner, during December, snow falls for 12.5 days and regularly aggregates up to 4.61" (117mm) of snow. In Sumner, during the entire year, snow falls for 55.9 days and aggregates up to 23.46" (596mm) of snow.Daylight
With an average of 9h and 6min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:20 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:39 am and sunset at 4:44 pm CST.
Sunshine
The average sunshine in December is 4.1h.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: The daily high UV index of 1 in December translates into this advice:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. Given the potency of the midday Sun's UV radiation, one should avoid prolonged exposure. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Forewarned is forearmed! The Sun's UV radiation can be almost doubled in intensity by snow reflection.
Frequently asked questions
How cold is December in Sumner?
What is the average humidity in December in Sumner?
How much does it rain in Sumner in December?
How many days does it snow in December in Sumner?
What is the month with the shortest days in Sumner?
How many hours of daylight does Sumner have in December?
What time are sunrise and sunset in December in Sumner?
How many hours of sunshine does Sumner have in December?
When is the lowest UV index in Sumner?
What is the UV index intensity in December in Sumner?
Average temperature in December
Sumner, IA
- Average high temperature in December: 29.8°F
The warmest month (with the highest average high temperature) is July (79.2°F).
The month with the lowest average high temperature is January (23.5°F).
- Average low temperature in December: 19.4°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (11.1°F).
Average pressure in December
Sumner, IA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in December
Sumner, IA
- Average wind speed in December: 10.1mph
The windiest month (with the highest average wind speed) is April (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in December
Sumner, IA
- Average humidity in December: 84%
The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is October (73%).
Average rainfall in December
Sumner, IA
- Average rainfall in December: 1.61"
The wettest month (with the highest rainfall) is June (5.04").
The driest month (with the least rainfall) is January (1.14").
Average rainfall days in December
Sumner, IA
- Average rainfall days in December: 6.4 days
The month with the highest number of rainy days is May (20.3 days).
The months with the least rainy days are January and February (4.3 days).
Average snowfall in December
Sumner, IA
- Average snowfall in December: 4.61"
The month with the highest snowfall is February (5.83").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Sumner, IA
- Average snowfall days in December: 12.5 days
The month with the highest number of snowfall days is January (13.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Sumner, 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 months with the most sunshine are July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in December
Sumner, IA
- Average sunshine days in December: 15.5 days
The month with the most sunshine days is November (16.8 days).
The month with the least sunshine days is June (7.3 days).
Average UV index in December
Sumner, IA
- Average UV index in December: 1
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Sumner, 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
Sumner, IA
- Average visibility in December: 6mi
The months with the highest visibility are March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February and July (5mi).
Sumner, Iowa, USA
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