Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
The beginning of December marks a decrease in the average high-temperature, transitioning from a chilly 47.1°F (8.4°C) in November to an icy 34.5°F (1.4°C). The average temperature during December nights is registered at a freezing cold 24.1°F (-4.4°C).Humidity
In December, the average relative humidity in Castle Junction, Illinois, is 81%.Rainfall
December is the month with the least rainfall. Rain falls for 6.6 days and accumulates 0.75" (19mm) of precipitation.Snowfall
Months with snowfall are January through April, October through December. In Castle Junction, Illinois, in December, snow falls for 7.8 days, with typically accumulated 1.42" (36mm) of snow. Throughout the year, there are 35.4 snowfall days, and 8.35" (212mm) of snow is accumulated.Daylight
December has the shortest days of the year in Castle Junction, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 7:09 am and sunset at 4:33 pm. On the last day of December, in Castle Junction, sunrise is at 7:28 am and sunset at 4:43 pm CST.
Sunshine
The average sunshine in December in Castle Junction is 4.4h.UV index
In December, the average daily maximum UV index in Castle Junction, Illinois, is 2. A UV Index estimate of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the average person.Note: The maximum UV index of 2 during December leads to these instructions:
Extended exposure to the sun should always be avoided by children, infants, and those with sensitive skin. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration. Forewarned is forearmed! The Sun's UV radiation can be almost doubled in intensity by snow reflection.
Frequently asked questions
How cold is December in Castle Junction?
What is the average humidity in December in Castle Junction?
What is the driest month in Castle Junction?
How many days does it rain in December in Castle Junction?
How much does it snow in Castle Junction in December?
What is the month with the shortest days in Castle Junction?
What is the average length of the day in December in Castle Junction?
When are sunrise and sunset in December in Castle Junction?
How many hours of sunshine does Castle Junction have in December?
What is the UV index intensity in December in Castle Junction?
Average temperature in December
Castle Junction, IL
- Average high temperature in December: 34.5°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.2°F).
- Average low temperature in December: 24.1°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (16.2°F).
Average pressure in December
Castle Junction, 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 (29.9"Hg).
Average wind speed in December
Castle Junction, 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 (6.7mph).
Average humidity in December
Castle Junction, IL
- Average humidity in December: 81%
The months with the highest relative humidity are January and July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Castle Junction, IL
- Average rainfall in December: 0.75"
The wettest month (with the highest rainfall) is May (3.31").
The driest month (with the least rainfall) is December (0.75").
Average rainfall days in December
Castle Junction, IL
- Average rainfall days in December: 6.6 days
The month with the highest number of rainy days is June (17 days).
The month with the least rainy days is January (4.2 days).
Average snowfall in December
Castle Junction, IL
- Average snowfall in December: 1.42"
The month with the highest snowfall is February (2.52").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Castle Junction, IL
- Average snowfall days in December: 7.8 days
The month with the highest number of snowfall days is January (10.3 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
Castle Junction, IL
- Average daylight in December: 9h and 1min
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 12min).
- Average sunshine in December: 4h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Castle Junction, IL
- Average sunshine days in December: 18.6 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is June (10.8 days).
Average UV index in December
Castle Junction, IL
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in December
Castle Junction, IL
- Average cloud cover in December: 54
The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in December
Castle Junction, 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).
Castle Junction, Illinois, USA
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