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 December begins, there is a decrease in the average high-temperature, falling from a frosty 44.6°F (7°C) in November to a cold 32.7°F (0.4°C). During December, Sunnyside witnesses a consistent average low-temperature of 22.8°F (-5.1°C).Humidity
The average relative humidity in December is 82%.Rainfall
The month with the least rainfall is December, when the rain falls for 7.9 days and typically collects 1.34" (34mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Sunnyside, during December, snow falls for 10.3 days and regularly aggregates up to 2.6" (66mm) of snow. Throughout the year, there are 49 snowfall days, and 16.5" (419mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 6min of daylight.On the first day of the month, sunrise is at 7:03 am and sunset at 4:21 pm. On the last day of December, sunrise is at 7:22 am and sunset at 4:30 pm CST.
Sunshine
In December, the average sunshine is 4h.UV index
January and December, with an average maximum UV index of 1, are months with the lowest UV index in Sunnyside. A UV Index value of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for the average person.Note: The UV index of 1 during December leads to these advisories:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
What is the driest month in Sunnyside?
How much does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When are sunrise and sunset in December in Sunnyside?
How many hours of sunshine does Sunnyside have in December?
What is the month with the lowest UV index?
What is the UV index reading in December?
Average temperature in December
Sunnyside, IL
- Average high temperature in December: 32.7°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 (26.6°F).
- Average low temperature in December: 22.8°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 (14.9°F).
Average pressure in December
Sunnyside, IL
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Sunnyside, IL
- Average wind speed in December: 9.3mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in December
Sunnyside, IL
- Average humidity in December: 82%
The months with the highest relative humidity are January and February (85%).
The month with the lowest relative humidity is October (76%).
Average rainfall in December
Sunnyside, IL
- Average rainfall in December: 1.34"
The wettest month (with the highest rainfall) is June (3.58").
The driest month (with the least rainfall) is December (1.34").
Average rainfall days in December
Sunnyside, IL
- Average rainfall days in December: 7.9 days
The month with the highest number of rainy days is July (18.3 days).
The month with the least rainy days is February (4.9 days).
Average snowfall in December
Sunnyside, IL
- Average snowfall in December: 2.6"
The month with the highest snowfall is January (5.16").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Sunnyside, IL
- Average snowfall days in December: 10.3 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
Sunnyside, IL
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 0min
The months with the most sunshine are July and August (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Sunnyside, IL
- Average sunshine days in December: 15.9 days
The month with the most sunshine days is November (16 days).
The month with the least sunshine days is June (10.2 days).
Average UV index in December
Sunnyside, IL
- Average UV index in December: 1
The month with the highest UV index is August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Sunnyside, IL
- Average cloud cover in December: 60
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 31).
Average visibility in December
Sunnyside, IL
- Average visibility in December: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
Sunnyside, Illinois, USA
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