December weather forecastFairfield, IL
December
Weather in December
The first month of the winter, December, is also a frosty month in Fairfield, Illinois, with an average temperature fluctuating between 43.2°F (6.2°C) and 31.1°F (-0.5°C).Temperature
December's onset corresponds with a shift in the average high-temperature, moving from a fresh 52.9°F (11.6°C) in November to a chilly 43.2°F (6.2°C). An average low-temperature of 31.1°F (-0.5°C) is expected during December.Humidity
In December, the average relative humidity is 78%.Rainfall
In Fairfield, in December, during 10.9 rainfall days, 2.68" (68mm) of precipitation is typically accumulated. Throughout the year, there are 166.4 rainfall days, and 37.32" (948mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 4.1 days. Throughout December, 1.42" (36mm) of snow is accumulated. In Fairfield, during the entire year, snow falls for 21.2 days and aggregates up to 6.97" (177mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 30min of daylight.On the first day of the month, sunrise is at 6:52 am and sunset at 4:33 pm. On the last day of December, sunrise is at 7:10 am and sunset at 4:43 pm CST.
Sunshine
The average sunshine in December is 4.6h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index estimate of 2, and below, represents a minimal health vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: The daily high UV index of 2 during December translates into the following recommendations:
In contrast to children, who must always be shielded from the sun, most people can tolerate up to an hour of sun exposure without any burns. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Fairfield, IL
- Average high temperature in December: 43.2°F
The warmest month (with the highest average high temperature) is July (85.1°F).
The month with the lowest average high temperature is January (37.8°F).
- Average low temperature in December: 31.1°F
The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (25°F).
Average pressure in December
Fairfield, IL
- Average pressure in December: 30.14"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Fairfield, IL
- Average wind speed in December: 9.1mph
The windiest months (with the highest average wind speed) are February and March (9.9mph).
The calmest month (with the lowest average wind speed) is July (5.9mph).
Average humidity in December
Fairfield, IL
- Average humidity in December: 78%
The months with the highest relative humidity are May and July (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in December
Fairfield, IL
- Average rainfall in December: 2.68"
The wettest month (with the highest rainfall) is April (4.96").
The driest month (with the least rainfall) is September (2.05").
Average rainfall days in December
Fairfield, IL
- Average rainfall days in December: 10.9 days
The month with the highest number of rainy days is May (19.8 days).
The month with the least rainy days is January (8.7 days).
Average snowfall in December
Fairfield, IL
- Average snowfall in December: 1.42"
The months with the highest snowfall are January and February (2.01").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Fairfield, IL
- Average snowfall days in December: 4.1 days
The month with the highest number of snowfall days is January (6.7 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
Fairfield, IL
- Average daylight in December: 9h and 30min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in December: 4h and 36min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in December
Fairfield, IL
- Average sunshine days in December: 17.6 days
The month with the most sunshine days is October (17.9 days).
The month with the least sunshine days is May (9 days).
Average UV index in December
Fairfield, IL
- Average UV index in December: 2
The months with the highest UV index are May, 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
Fairfield, IL
- Average cloud cover in December: 50
The months with the most cloud cover are January and February (Cloud cover 51).
The months with the least cloud cover are June and August (Cloud cover 28).
Average visibility in December
Fairfield, 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).





