December weather forecastGreen Valley, IL
December
Weather in December
The first month of the winter, December, is still a cold month in Green Valley, Illinois, with an average temperature ranging between min 26.4°F (-3.1°C) and max 36.9°F (2.7°C).Temperature
Green Valley, Illinois, experiences a temperature shift at the start of December, with average high-temperatures adjusting from a frosty 48.9°F (9.4°C) in November to a wintry 36.9°F (2.7°C). Green Valley records an average nighttime low of 26.4°F (-3.1°C) in December.Humidity
The average relative humidity in December is 79%.Rainfall
In Green Valley, Illinois, in December, it is raining for 6.6 days, with typically 1.06" (27mm) of accumulated precipitation. Throughout the year, there are 131.4 rainfall days, and 20.08" (510mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 5.4 days. Throughout December, 1.22" (31mm) of snow is accumulated. In Green Valley, during the entire year, snow falls for 25.8 days and aggregates up to 8.66" (220mm) of snow.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:03 am and sunset at 4:32 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 4:42 pm CST.
Sunshine
In Green Valley, the average sunshine in December is 4.4h.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 value of 2, and less, symbolizes a low health risk from unprotected exposure to Sun's UV rays for the ordinary person.Note: The daily maximum UV index of 2 in December interprets into the following advice:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation. Heed this! Snow reflection can almost augment the UV radiation of the sun by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Green Valley, IL
- Average high temperature in December: 36.9°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (31.5°F).
- Average low temperature in December: 26.4°F
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure in December
Green Valley, 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 (29.91"Hg).
Average wind speed in December
Green Valley, IL
- Average wind speed in December: 9.8mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in December
Green Valley, IL
- Average humidity in December: 79%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Green Valley, IL
- Average rainfall in December: 1.06"
The wettest month (with the highest rainfall) is May (2.83").
The driest month (with the least rainfall) is February (1.02").
Average rainfall days in December
Green Valley, IL
- Average rainfall days in December: 6.6 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (5.1 days).
Average snowfall in December
Green Valley, IL
- Average snowfall in December: 1.22"
The month with the highest snowfall is January (2.87").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Green Valley, IL
- Average snowfall days in December: 5.4 days
The month with the highest number of snowfall days is January (8.4 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
Green Valley, IL
- Average daylight in December: 9h and 18min
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 18min).
- Average sunshine in December: 4h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Green Valley, IL
- Average sunshine days in December: 19.7 days
The month with the most sunshine days is November (20 days).
The month with the least sunshine days is May (11.8 days).
Average UV index in December
Green Valley, 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
Green Valley, 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
Green Valley, 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).
