January weather forecastNaperville, IL

January
Weather in January
The city of Naperville welcomes the new year with cold and frosty weather conditions. The city witnesses a high of 28.4°F (-2°C) and a low of 17.1°F (-8.3°C). Snow showers blanket the city, making the cityscape resemble a picture-perfect winter postcard. With only 3.8 hours of sunshine, most days are cloudy and gray. The icy conditions persist throughout the month, providing a classic midwestern winter feel.Temperature
January is the coldest month of the year, registering average temperatures as high as 28.4°F (-2°C) and as low as 17.1°F (-8.3°C).Humidity
The months with the highest humidity are January and February, with an average relative humidity of 83%.Rainfall
In Naperville, in January, it is raining for 4.8 days, with typically 0.83" (21mm) of accumulated precipitation. Throughout the year, there are 132.2 rainfall days, and 16.22" (412mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall. The month with the most snowfall is January, when snow falls for 11.1 days and typically aggregates up to 1.85" (47mm) of snow.Daylight
In January, the average length of the day is 9h and 34min.On the first day of the month, sunrise is at 7:19 am and sunset at 4:32 pm. On the last day of January, sunrise is at 7:05 am and sunset at 5:06 pm CST.
Sunshine
January has the least sunshine of the year in Naperville, with an average of 3.8h of sunshine.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 1. A UV Index value of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for ordinary individuals.Note: In January, the maximum UV index of 1 suggests these recommendations:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Tightly woven clothing, when worn loosely, shields effectively against the Sun. Consider this! The reflection from snow can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Naperville, IL
- Average high temperature in January: 28.4°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 January: 17.1°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 January
Naperville, IL
- Average pressure in January: 30.11"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 January
Naperville, IL
- Average wind speed in January: 9.7mph
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 January
Naperville, IL
- Average humidity in January: 83%
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 January
Naperville, IL
- Average rainfall in January: 0.83"
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 January
Naperville, IL
- Average rainfall days in January: 4.8 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 January
Naperville, IL
- Average snowfall in January: 1.85"
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 January
Naperville, IL
- Average snowfall days in January: 11.1 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 January /
Average sunshine in January
Naperville, IL
- Average daylight in January: 9h and 36min
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 January: 3h and 48min
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 January
Naperville, IL
- Average sunshine days in January: 17.8 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 January
Naperville, IL
- Average UV index in January: 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 January
Naperville, IL
- Average cloud cover in January: 60
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 January
Naperville, IL
- Average visibility in January: 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).





