December weather forecastCountryside, IL
December
Weather in December
The first month of the winter, December, is also an icy month in Countryside, Illinois, with temperature in the range of an average high of 35.2°F (1.8°C) and an average low of 25.5°F (-3.6°C).Temperature
The onset of December is marked by a decrease in temperature, transitioning from a frosty 46.2°F (7.9°C) in November to a wintry 35.2°F (1.8°C). In the month of December, the temperature generally rests at an average low of 25.5°F (-3.6°C).Humidity
In December, the average relative humidity is 80%.Rainfall
The months with the least rainfall are November and December Rain falls for 8.5 days and accumulates 1.77" (45mm) of rain.Snowfall
Months with snowfall are January through April, October through December. In Countryside, during December, snow falls for 9.6 days and regularly aggregates up to 2.76" (70mm) of snow. Throughout the year, there are 47.1 snowfall days, and 19.02" (483mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 6:59 am and sunset at 4:21 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 4:31 pm CST.
Sunshine
In Countryside, the average sunshine in December is 4.1h.UV index
The month with the lowest UV index is December, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for average individuals.Note: A maximum UV index of 1 in December translates 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. In the presence of strong sunlight, it's crucial to wear sunglasses that ward off UVA and UVB rays. Be cautious! The UV radiation from the Sun can be magnified almost twofold by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Countryside, IL
- Average high temperature in December: 35.2°F
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (28.9°F).
- Average low temperature in December: 25.5°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (18.3°F).
Average pressure in December
Countryside, 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
Countryside, IL
- Average wind speed in December: 9.4mph
The windiest month (with the highest average wind speed) is January (10.2mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in December
Countryside, IL
- Average humidity in December: 80%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Countryside, IL
- Average rainfall in December: 1.77"
The wettest month (with the highest rainfall) is May (4.61").
The driest months (with the least rainfall) are November and December (1.77").
Average rainfall days in December
Countryside, IL
- Average rainfall days in December: 8.5 days
The month with the highest number of rainy days is June (19.4 days).
The month with the least rainy days is February (5.9 days).
Average snowfall in December
Countryside, IL
- Average snowfall in December: 2.76"
The month with the highest snowfall is February (5.28").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Countryside, IL
- Average snowfall days in December: 9.6 days
The month with the highest number of snowfall days is January (13.3 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Countryside, IL
- Average daylight in December: 9h and 12min
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 12min).
- Average sunshine in December: 4h and 6min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Countryside, IL
- Average sunshine days in December: 14.3 days
The month with the most sunshine days is November (16.1 days).
The month with the least sunshine days is June (8.2 days).
Average UV index in December
Countryside, IL
- Average UV index in December: 1
The months with the highest UV index are July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Countryside, IL
- Average cloud cover in December: 58
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in December
Countryside, 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).





