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 frosty 45.7°F (7.6°C) in November to a wintry 34.5°F (1.4°C). Westmont's nights in December experience an average temperature drop to a freezing cold 25°F (-3.9°C).Humidity
In December, the average relative humidity in Westmont is 81%.Rainfall
December is the month with the least rainfall in Westmont. Rain falls for 4.9 days and accumulates 0.63" (16mm) of precipitation.Snowfall
January through April, October through December are months with snowfall. In December, in Westmont, it is snowing for 7.2 days. Throughout December, 0.75" (19mm) of snow is accumulated. Throughout the year, there are 34.9 snowfall days, and 7.2" (183mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 7:00 am and sunset at 4:21 pm. On the last day of December, in Westmont, sunrise is at 7:19 am and sunset at 4:31 pm CST.
Sunshine
In Westmont, the average sunshine in December is 4.1h.UV index
In Westmont, the average daily maximum UV index in December is 2. A UV Index estimate of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: The UV index of 2 during December leads to these advisories:
Sun exposure does not present considerable issues for many, yet infants, fair-skinned people, and children necessitate constant protection. When the Sun is at its strongest around midday, find shade and limit exposure. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.
Frequently asked questions
How cold is December in Westmont?
What is the average humidity in December in Westmont?
What is the driest month in Westmont?
How much does it rain in Westmont in December?
How much does it snow in Westmont in December?
What is the month with the shortest days in Westmont?
What is the average length of the day in December in Westmont?
When are sunrise and sunset in December in Westmont?
How long on average sun shines in December in Westmont?
How high is the UV index in December in Westmont?
Average temperature in December
Westmont, IL
- Average high temperature in December: 34.5°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in December: 25°F
The month with the highest average low temperature is July (66.4°F).
The coldest month (with the lowest average low temperature) is January (17.1°F).
Average pressure in December
Westmont, IL
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Westmont, IL
- Average wind speed in December: 9mph
The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest month (with the lowest average wind speed) is August (6.1mph).
Average humidity in December
Westmont, IL
- Average humidity in December: 81%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Westmont, IL
- Average rainfall in December: 0.63"
The wettest month (with the highest rainfall) is May (1.97").
The driest month (with the least rainfall) is December (0.63").
Average rainfall days in December
Westmont, IL
- Average rainfall days in December: 4.9 days
The month with the highest number of rainy days is May (14.9 days).
The month with the least rainy days is February (4.2 days).
Average snowfall in December
Westmont, IL
- Average snowfall in December: 0.75"
The month with the highest snowfall is February (2.28").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Westmont, IL
- Average snowfall days in December: 7.2 days
The month with the highest number of snowfall days is January (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Westmont, 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 1min
The month with the most sunshine is August (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Westmont, IL
- Average sunshine days in December: 20.7 days
The month with the most sunshine days is December (20.7 days).
The month with the least sunshine days is July (11.8 days).
Average UV index in December
Westmont, IL
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in December
Westmont, IL
- Average cloud cover in December: 59
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in December
Westmont, 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).
Westmont, Illinois, USA
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