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 transition into December is accompanied by a temperature decrease, with the average high-temperature shifting from a chilly 47.7°F (8.7°C) in November to a cold 36.5°F (2.5°C). In December, Gillum experiences an average nighttime temperature of 26.1°F (-3.3°C).Humidity
The average relative humidity in December is 80%.Rainfall
The month with the least rainfall is December, when the rain falls for 9 days and typically collects 1.93" (49mm) of precipitation.Snowfall
January through April, October through December are months with snowfall. In December, it is snowing for 8.2 days. Throughout December, 2.64" (67mm) of snow is accumulated. In Gillum, Illinois, during the entire year, snow falls for 40.7 days and aggregates up to 17.01" (432mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:00 am and sunset at 4:29 pm. On the last day of the month, sunrise is at 7:18 am and sunset at 4:39 pm CST.
Sunshine
In Gillum, the average sunshine in December is 4.2h.UV index
The months with the lowest UV index are January, February, October through December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low health risk from unsafe exposure to UV radiation for ordinary individuals.Note: The maximum UV index of 2 during December leads to these instructions:
While most individuals can withstand prolonged sun exposure, it is imperative that babies, children, and those with sensitive skin always be shielded. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
What is the driest month?
How much does it rain in December?
How many days does it snow in December in Gillum?
What is the month with the shortest days?
What is the average length of the day in December in Gillum?
When is the sunrise / sunset in December?
How long on average sun shines in December?
What is the month with the lowest UV index in Gillum?
What is the UV index reading in December?
Average temperature in December
Gillum, IL
- Average high temperature in December: 36.5°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (30.7°F).
- Average low temperature in December: 26.1°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 (18.9°F).
Average pressure in December
Gillum, 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 (29.92"Hg).
Average wind speed in December
Gillum, IL
- Average wind speed in December: 10.6mph
The windiest month (with the highest average wind speed) is January (11.1mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in December
Gillum, IL
- Average humidity in December: 80%
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Gillum, IL
- Average rainfall in December: 1.93"
The wettest month (with the highest rainfall) is May (4.57").
The driest month (with the least rainfall) is December (1.93").
Average rainfall days in December
Gillum, IL
- Average rainfall days in December: 9 days
The month with the highest number of rainy days is May (20.1 days).
The month with the least rainy days is February (6.9 days).
Average snowfall in December
Gillum, IL
- Average snowfall in December: 2.64"
The month with the highest snowfall is January (5.04").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Gillum, IL
- Average snowfall days in December: 8.2 days
The month with the highest number of snowfall days is January (12.8 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
Gillum, IL
- Average daylight in December: 9h and 2min
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 1min
The month with the most sunshine is June (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Gillum, IL
- Average sunshine days in December: 15 days
The month with the most sunshine days is November (17.4 days).
The month with the least sunshine days is May (8.4 days).
Average UV index in December
Gillum, 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, October, November and December (UV index 2).
Average cloud cover in December
Gillum, IL
- Average cloud cover in December: 56
The month with the most cloud cover is January (Cloud cover 60).
The months with the least cloud cover are August and September (Cloud cover 33).
Average visibility in December
Gillum, IL
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).
Gillum, Illinois, USA
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