December weather forecastKnoxville, IL
December
Weather in December
The first month of the winter, December, is also an icy month in Knoxville, Illinois, with an average temperature varying between 24.6°F (-4.1°C) and 35.4°F (1.9°C).Temperature
Onset of December witnesses a reduction in the average high-temperature, falling from a chilly 47.5°F (8.6°C) in November to a wintry 35.4°F (1.9°C). Knoxville experiences an average temperature drop to a subzero cold 24.6°F (-4.1°C) during December nights.Humidity
The average relative humidity in December is 81%.Rainfall
January and December are months with the least rain in Knoxville when the rain falls for 4.5 days and typically aggregates up to 0.47" (12mm) of rain.Snowfall
January through April, October through December are months with snowfall. In Knoxville, during December, snow falls for 6 days and regularly aggregates up to 0.43" (11mm) of snow. Throughout the year, there are 28 snowfall days, and 4.53" (115mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:07 am and sunset at 4:33 pm. On the last day of the month, sunrise is at 7:25 am and sunset at 4:43 pm CST.
Sunshine
In December, the average sunshine is 4.4h.UV index
The month with the lowest UV index is December, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: In December, an average UV index of 1 transforms into the following instructions:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Take warning! The intensity of the Sun's UV radiation can be nearly amplified twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Knoxville, IL
- Average high temperature in December: 35.4°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (29.5°F).
- Average low temperature in December: 24.6°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (17.4°F).
Average pressure in December
Knoxville, IL
- Average pressure in December: 30.11"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
Knoxville, IL
- Average wind speed in December: 9.9mph
The windiest month (with the highest average wind speed) is April (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (6.8mph).
Average humidity in December
Knoxville, IL
- Average humidity in December: 81%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Knoxville, IL
- Average rainfall in December: 0.47"
The wettest month (with the highest rainfall) is May (1.65").
The driest months (with the least rainfall) are January and December (0.47").
Average rainfall days in December
Knoxville, IL
- Average rainfall days in December: 4.5 days
The month with the highest number of rainy days is May (15.2 days).
The month with the least rainy days is February (3.9 days).
Average snowfall in December
Knoxville, IL
- Average snowfall in December: 0.43"
The month with the highest snowfall is January (1.38").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Knoxville, IL
- Average snowfall days in December: 6 days
The month with the highest number of snowfall days is January (8.8 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
Knoxville, IL
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
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 6min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Knoxville, IL
- Average sunshine days in December: 21.6 days
The month with the most sunshine days is December (21.6 days).
The month with the least sunshine days is June (12.4 days).
Average UV index in December
Knoxville, IL
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Knoxville, IL
- Average cloud cover in December: 54
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility in December
Knoxville, IL
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
