December weather forecastGrand Tower, IL
December
Weather in December
December, the first month of the winter in Grand Tower, is still a chilly month, with an average temperature ranging between max 43.7°F (6.5°C) and min 31.8°F (-0.1°C).Temperature
December's onset corresponds with a shift in the average high-temperature, moving from a fresh 54°F (12.2°C) in November to a frosty 43.7°F (6.5°C). The average low-temperature during December nights is a subzero cold 31.8°F (-0.1°C).Humidity
In December, the average relative humidity in Grand Tower is 77%.Rainfall
In Grand Tower, in December, it is raining for 10.3 days, with typically 2.2" (56mm) of accumulated precipitation. Throughout the year, in Grand Tower, there are 158.6 rainfall days, and 34.69" (881mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall in Grand Tower. In Grand Tower, Illinois, in December, snow falls for 3 days, with typically accumulated 1.26" (32mm) of snow. Throughout the year, in Grand Tower, there are 15.9 snowfall days, and 5.71" (145mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 36min of daylight.On the first day of the month, sunrise is at 6:54 am and sunset at 4:39 pm. On the last day of December, in Grand Tower, sunrise is at 7:12 am and sunset at 4:49 pm CST.
Sunshine
The average sunshine in December is 4.8h.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 unsafe exposure to UV radiation for average individuals.Note: The UV index of 2 during December leads to these advisories:
It is important to always shield children, babies, and individuals with sensitive skin from prolonged exposure to the sun. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Grand Tower, IL
- Average high temperature in December: 43.7°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is January (39.6°F).
- Average low temperature in December: 31.8°F
The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (26.2°F).
Average pressure in December
Grand Tower, 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 (29.93"Hg).
Average wind speed in December
Grand Tower, IL
- Average wind speed in December: 8.6mph
The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in December
Grand Tower, IL
- Average humidity in December: 77%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Grand Tower, IL
- Average rainfall in December: 2.2"
The wettest month (with the highest rainfall) is April (4.49").
The driest month (with the least rainfall) is September (1.85").
Average rainfall days in December
Grand Tower, IL
- Average rainfall days in December: 10.3 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is January (9.4 days).
Average snowfall in December
Grand Tower, IL
- Average snowfall in December: 1.26"
The month with the highest snowfall is February (1.73").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Grand Tower, IL
- Average snowfall days in December: 3 days
The months with the highest number of snowfall days are January and February (4.8 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
Grand Tower, IL
- Average daylight in December: 9h and 36min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 4h and 48min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in December
Grand Tower, IL
- Average sunshine days in December: 18.4 days
The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is May (11.3 days).
Average UV index in December
Grand Tower, 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
Grand Tower, IL
- Average cloud cover in December: 48
The month with the most cloud cover is February (Cloud cover 50).
The months with the least cloud cover are June and August (Cloud cover 27).
Average visibility in December
Grand Tower, 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).





