December weather forecastGlen Carbon, IL
December
Weather in December
The first month of the winter, December, is also an icy month in Glen Carbon, Illinois, with an average temperature ranging between max 41.9°F (5.5°C) and min 30°F (-1.1°C).Temperature
The average high-temperature drops in December, from November's cool 52.9°F (11.6°C) to a wintry 41.9°F (5.5°C). Glen Carbon records an average nighttime low-temperature of 30°F (-1.1°C) throughout December.Humidity
The average relative humidity in December is 77%.Rainfall
In Glen Carbon, Illinois, in December, during 8.4 rainfall days, 2.2" (56mm) of precipitation is typically accumulated. Throughout the year, in Glen Carbon, there are 149.9 rainfall days, and 33.94" (862mm) of precipitation is accumulated.Snowfall
January through March, September, November and December are months with snowfall in Glen Carbon. In Glen Carbon, in December, snow falls for 3.8 days, with typically accumulated 1.73" (44mm) of snow. In Glen Carbon, Illinois, during the entire year, snow falls for 20.7 days and aggregates up to 7.13" (181mm) of snow.Daylight
With an average of 9h and 30min of daylight, December has the shortest days of the year in Glen Carbon.On the first day of December in Glen Carbon, Illinois, sunrise is at 6:59 am and sunset at 4:38 pm. On the last day of the month, sunrise is at 7:17 am and sunset at 4:48 pm CST.
Sunshine
The average sunshine in December in Glen Carbon is 4.8h.UV index
The months with the lowest UV index 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 threat to health from unsafe exposure to UV radiation for the ordinary person.Note: The maximum UV index of 2 during December translates into these guidelines:
Long-term sun exposure is typically not a concern for most. However, those with sensitive skin, infants, and children must always have protection. Avoiding the Sun during its peak radiation time around midday is a healthy practice. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Caution! The reflection of snow can nearly 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 December
Glen Carbon, IL
- Average high temperature in December: 41.9°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.4°F).
- Average low temperature in December: 30°F
The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).
Average pressure in December
Glen Carbon, IL
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Glen Carbon, IL
- Average wind speed in December: 8.8mph
The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest month (with the lowest average wind speed) is July (5.6mph).
Average humidity in December
Glen Carbon, IL
- Average humidity in December: 77%
The months with the highest relative humidity are May, July and August (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Glen Carbon, IL
- Average rainfall in December: 2.2"
The wettest month (with the highest rainfall) is May (4.17").
The driest month (with the least rainfall) is February (1.77").
Average rainfall days in December
Glen Carbon, IL
- Average rainfall days in December: 8.4 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is January (7.8 days).
Average snowfall in December
Glen Carbon, IL
- Average snowfall in December: 1.73"
The month with the highest snowfall is January (2.13").
The months with the least snowfall are April, May, June, July, August and October (0").
Average snowfall days in December
Glen Carbon, IL
- Average snowfall days in December: 3.8 days
The month with the highest number of snowfall days is January (7 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Glen Carbon, 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 48min
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 30min).
Average sunshine days in December
Glen Carbon, IL
- Average sunshine days in December: 18.6 days
The month with the most sunshine days is December (18.6 days).
The month with the least sunshine days is May (11.6 days).
Average UV index in December
Glen Carbon, 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
Glen Carbon, IL
- Average cloud cover in December: 49
The month with the most cloud cover is January (Cloud cover 51).
The months with the least cloud cover are June and August (Cloud cover 28).
Average visibility in December
Glen Carbon, 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).
