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 involves a decrease in the average high-temperature, falling from a frosty 45.3°F (7.4°C) in November to a wintry 33.6°F (0.9°C). Vernon Hills's nights in December experience an average temperature drop to a subzero cold 24.3°F (-4.3°C).Humidity
The average relative humidity in December is 81%.Rainfall
The months with the least rainfall are November and December Rain falls for 7.8 days and accumulates 1.3" (33mm) of rain.Snowfall
January through May, October through December are months with snowfall. In Vernon Hills, in December, snow falls for 10.4 days, with typically accumulated 3.03" (77mm) of snow. In Vernon Hills, during the entire year, snow falls for 48.2 days and aggregates up to 18.86" (479mm) of snow.Daylight
With an average of 9h and 12min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:01 am and sunset at 4:20 pm. On the last day of the month, sunrise is at 7:20 am and sunset at 4:29 pm CST.
Sunshine
In December, the average sunshine is 4h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a low threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In December, the maximum UV index of 1 suggests this advice:
While many people can endure lengthy sun exposure, it remains imperative to safeguard babies, children, and fair-skinned individuals. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. Be vigilant! The reflective nature of snow can increase the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in December?
What is the average humidity in December?
What is the driest month?
How many days does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Vernon Hills have in December?
What time are sunrise and sunset in December?
How long on average sun shines in December?
What is the month with the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Vernon Hills, IL
- Average high temperature in December: 33.6°F
The warmest month (with the highest average high temperature) is July (80.4°F).
The month with the lowest average high temperature is January (27.9°F).
- Average low temperature in December: 24.3°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 (16.5°F).
Average pressure in December
Vernon Hills, IL
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Vernon Hills, IL
- Average wind speed in December: 9.5mph
The windiest month (with the highest average wind speed) is January (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in December
Vernon Hills, IL
- Average humidity in December: 81%
The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall in December
Vernon Hills, IL
- Average rainfall in December: 1.3"
The wettest month (with the highest rainfall) is June (3.54").
The driest months (with the least rainfall) are November and December (1.3").
Average rainfall days in December
Vernon Hills, IL
- Average rainfall days in December: 7.8 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in December
Vernon Hills, IL
- Average snowfall in December: 3.03"
The month with the highest snowfall is February (5.55").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Vernon Hills, IL
- Average snowfall days in December: 10.4 days
The month with the highest number of snowfall days is January (12.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Vernon Hills, IL
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 4h and 0min
The months with the most sunshine are July and August (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Vernon Hills, IL
- Average sunshine days in December: 14.5 days
The month with the most sunshine days is November (16.6 days).
The month with the least sunshine days is June (10 days).
Average UV index in December
Vernon Hills, IL
- Average UV index in December: 1
The months with the highest UV index are July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Vernon Hills, IL
- Average cloud cover in December: 59
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are July and August (Cloud cover 30).
Average visibility in December
Vernon Hills, IL
- Average visibility in December: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
Vernon Hills, Illinois, USA
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