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 shift from November to December corresponds with a decrease in the average high-temperature, down to an icy 33.8°F (1°C) from a chilly 45.5°F (7.5°C). In Harmon, the average temperature during the nights of December drops to a subzero cold 23.2°F (-4.9°C).Humidity
In Harmon, Illinois, the average relative humidity in December is 82%.Rainfall
In Harmon, in December, it is raining for 5.7 days, with typically 0.83" (21mm) of accumulated precipitation. Throughout the year, in Harmon, there are 130.2 rainfall days, and 17.36" (441mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall. In Harmon, in December, during 7.4 snowfall days, 1.3" (33mm) of snow is typically accumulated. In Harmon, Illinois, during the entire year, snow falls for 34.2 days and aggregates up to 7.87" (200mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of December in Harmon, Illinois, sunrise is at 7:06 am and sunset at 4:28 pm. On the last day of the month, sunrise is at 7:25 am and sunset at 4:37 pm CST.
Sunshine
In December, the average sunshine is 4.1h.UV index
The month with the lowest UV index is December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for average individuals.Note: A maximum high daily UV index of 1 during December translates into the following directions:
Most individuals can handle sun exposure for up to an hour without burning, but children must always be shielded from sun exposure. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December in Harmon?
What is the average humidity in December in Harmon?
How many days does it rain in December in Harmon?
How many days does it snow in December in Harmon?
What is the month with the shortest days in Harmon?
How many hours of daylight does Harmon have in December?
What time are sunrise and sunset in December in Harmon?
How long on average sun shines in December in Harmon?
When is the lowest UV index in Harmon?
How high is the UV index in December in Harmon?
Average temperature in December
Harmon, IL
- Average high temperature in December: 33.8°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (27.7°F).
- Average low temperature in December: 23.2°F
The month with the highest average low temperature is July (63.9°F).
The coldest month (with the lowest average low temperature) is January (14.9°F).
Average pressure in December
Harmon, IL
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Harmon, IL
- Average wind speed in December: 9.5mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in December
Harmon, IL
- Average humidity in December: 82%
The months with the highest relative humidity are January and July (85%).
The month with the lowest relative humidity is October (73%).
Average rainfall in December
Harmon, IL
- Average rainfall in December: 0.83"
The wettest month (with the highest rainfall) is May (2.83").
The driest months (with the least rainfall) are January and February (0.75").
Average rainfall days in December
Harmon, IL
- Average rainfall days in December: 5.7 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall in December
Harmon, IL
- Average snowfall in December: 1.3"
The month with the highest snowfall is January (2.56").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Harmon, IL
- Average snowfall days in December: 7.4 days
The month with the highest number of snowfall days is January (10.2 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
Harmon, 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 July (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in December
Harmon, IL
- Average sunshine days in December: 18.8 days
The months with the most sunshine days are November and December (18.8 days).
The month with the least sunshine days is June (11.3 days).
Average UV index in December
Harmon, IL
- Average UV index in December: 1
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Harmon, IL
- Average cloud cover in December: 57
The month with the most cloud cover is January (Cloud cover 60).
The month with the least cloud cover is September (Cloud cover 31).
Average visibility in December
Harmon, IL
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Harmon, Illinois, USA
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