December weather forecastWillow Hill, IL
December
Weather in December
The first month of the winter, December, is also an icy month in Willow Hill, Illinois, with an average temperature ranging between max 41.2°F (5.1°C) and min 29.7°F (-1.3°C).Temperature
The decrease of average high-temperatures is mild in December, with a decline from a fresh 51.3°F (10.7°C) in November to an icy 41.2°F (5.1°C). Willow Hill's temperature drops to an average low of 29.7°F (-1.3°C) during the nights of December.Humidity
In Willow Hill, the average relative humidity in December is 79%.Rainfall
In December, the rain falls for 10.6 days. Throughout December, 2.52" (64mm) of precipitation is accumulated. In Willow Hill, during the entire year, the rain falls for 158.3 days and collects up to 35.12" (892mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 3.8 days. Throughout December, 1.18" (30mm) of snow is accumulated. Throughout the year, there are 20.7 snowfall days, and 7.13" (181mm) of snow is accumulated.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 4:30 pm. On the last day of December, sunrise is at 7:10 am and sunset at 4:40 pm CST.
Sunshine
The average sunshine in December is 4.5h.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 value of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV rays for average individuals.Note: The daily maximum UV index of 2 in December interprets into the following advice:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Willow Hill, IL
- Average high temperature in December: 41.2°F
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is January (36°F).
- Average low temperature in December: 29.7°F
The month with the highest average low temperature is July (66.9°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).
Average pressure in December
Willow Hill, 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 (29.93"Hg).
Average wind speed in December
Willow Hill, IL
- Average wind speed in December: 9.4mph
The windiest months (with the highest average wind speed) are January and February (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).
Average humidity in December
Willow Hill, IL
- Average humidity in December: 79%
The months with the highest relative humidity are July and August (81%).
The month with the lowest relative humidity is October (70%).
Average rainfall in December
Willow Hill, IL
- Average rainfall in December: 2.52"
The wettest month (with the highest rainfall) is April (5.04").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Willow Hill, IL
- Average rainfall days in December: 10.6 days
The month with the highest number of rainy days is May (18.7 days).
The months with the least rainy days are January and February (9.3 days).
Average snowfall in December
Willow Hill, IL
- Average snowfall in December: 1.18"
The month with the highest snowfall is January (2.6").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Willow Hill, IL
- Average snowfall days in December: 3.8 days
The month with the highest number of snowfall days is January (6.3 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
Willow Hill, IL
- Average daylight in December: 9h and 30min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in December: 4h and 30min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in December
Willow Hill, IL
- Average sunshine days in December: 17.8 days
The month with the most sunshine days is October (18.2 days).
The month with the least sunshine days is May (10.1 days).
Average UV index in December
Willow Hill, 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
Willow Hill, IL
- Average cloud cover in December: 52
The month with the most cloud cover is January (Cloud cover 54).
The month with the least cloud cover is June (Cloud cover 29).
Average visibility in December
Willow Hill, 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).





