December weather forecastNaperville, IL
December
Weather in December
The weather in Naperville takes a sharp turn heading to the holiday season in December. Chilly yet festive, the city's weather ventures into colder territory, with an average high of 34.3°F (1.3°C) and a low of 24.4°F (-4.2°C). As snowflakes begin to touch upon the city, Naperville dresses itself in holiday décor, creating a magical winter atmosphere.Temperature
The beginning of December in Naperville involves a decrease in the average high-temperature, transitioning from a frosty 45.9°F (7.7°C) in November to a cold 34.3°F (1.3°C). Naperville, in December, witnesses an average low-temperature of 24.4°F (-4.2°C).Humidity
In December, the average relative humidity is 82%.Rainfall
December is the month with the least rainfall. Rain falls for 6.4 days and accumulates 0.71" (18mm) of precipitation.Snowfall
January through April, October through December are months with snowfall in Naperville. In Naperville, Illinois, in December, during 8.1 snowfall days, 1.02" (26mm) of snow is typically accumulated. Throughout the year, there are 38.7 snowfall days, and 6.93" (176mm) of snow is accumulated.Daylight
With an average of 9h and 12min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:00 am and sunset at 4:22 pm. On the last day of December, sunrise is at 7:19 am and sunset at 4:32 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 of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: The daily high UV index of 1 during December translates into the following recommendations:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. To guard against the harmful effects of the Sun, minimize exposure during midday. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration. Guard yourself! Snow reflection can almost double the UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Naperville, IL
- Average high temperature in December: 34.3°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.4°F).
- Average low temperature in December: 24.4°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (17.1°F).
Average pressure in December
Naperville, 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
Naperville, IL
- Average wind speed in December: 9.1mph
The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity in December
Naperville, IL
- Average humidity in December: 82%
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (73%).
Average rainfall in December
Naperville, IL
- Average rainfall in December: 0.71"
The wettest month (with the highest rainfall) is May (2.09").
The driest month (with the least rainfall) is December (0.71").
Average rainfall days in December
Naperville, IL
- Average rainfall days in December: 6.4 days
The month with the highest number of rainy days is July (17.3 days).
The month with the least rainy days is February (4.4 days).
Average snowfall in December
Naperville, IL
- Average snowfall in December: 1.02"
The month with the highest snowfall is January (1.85").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Naperville, IL
- Average snowfall days in December: 8.1 days
The month with the highest number of snowfall days is January (11.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Naperville, 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 12min
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 48min).
Average sunshine days in December
Naperville, IL
- Average sunshine days in December: 19.1 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is July (10.2 days).
Average UV index in December
Naperville, IL
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Naperville, IL
- Average cloud cover in December: 58
The month with the most cloud cover is January (Cloud cover 60).
The months with the least cloud cover are August and September (Cloud cover 31).
Average visibility in December
Naperville, IL
- 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).
