December weather forecastAtlanta, IL
December
Weather in December
The first month of the winter, December, is also a wintry month in Atlanta, Illinois, with an average temperature fluctuating between 27°F (-2.8°C) and 37.4°F (3°C).Temperature
The transition into December is accompanied by a temperature decrease, with the average high-temperature shifting from a chilly 49.1°F (9.5°C) in November to a cold 37.4°F (3°C). During the month of December, Atlanta's nighttime temperature lowers to an average of 27°F (-2.8°C).Humidity
The average relative humidity in December is 79%.Rainfall
The month with the least rainfall is December, when the rain falls for 7.2 days and typically collects 0.87" (22mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 5.3 days. Throughout December, 0.91" (23mm) of snow is accumulated. In Atlanta, during the entire year, snow falls for 27.1 days and aggregates up to 7.2" (183mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 24min of daylight.On the first day of December, sunrise is at 7:00 am and sunset at 4:31 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 4:41 pm CST.
Sunshine
The average sunshine in December is 4.5h.UV index
The months with the lowest UV index in Atlanta are January, February, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low health risk from unsafe exposure to UV radiation for the ordinary person.Note: The maximum daily UV index of 2 during December translates into the following directions:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. Avoid the Sun's strongest UV rays by seeking shade and limiting exposure during midday. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Alert! The snow's reflection can amplify the UV radiation of the Sun nearly twice.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Atlanta, IL
- Average high temperature in December: 37.4°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (31.6°F).
- Average low temperature in December: 27°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 (19.8°F).
Average pressure in December
Atlanta, IL
- Average pressure in December: 30.12"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Atlanta, IL
- Average wind speed in December: 9.9mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in December
Atlanta, IL
- Average humidity in December: 79%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (70%).
Average rainfall in December
Atlanta, IL
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is May (2.2").
The driest month (with the least rainfall) is December (0.87").
Average rainfall days in December
Atlanta, IL
- Average rainfall days in December: 7.2 days
The month with the highest number of rainy days is May (16.5 days).
The month with the least rainy days is February (5.9 days).
Average snowfall in December
Atlanta, IL
- Average snowfall in December: 0.91"
The month with the highest snowfall is January (2.2").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Atlanta, IL
- Average snowfall days in December: 5.3 days
The month with the highest number of snowfall days is January (9.5 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
Atlanta, IL
- Average daylight in December: 9h and 24min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in December: 4h and 30min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Atlanta, IL
- Average sunshine days in December: 20 days
The months with the most sunshine days are November and December (20 days).
The month with the least sunshine days is May (11.6 days).
Average UV index in December
Atlanta, IL
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Atlanta, IL
- Average cloud cover in December: 53
The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility in December
Atlanta, IL
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
