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
Onset of December comes with a temperature decline, the average high falling from a frosty 44.1°F (6.7°C) in November to a wintry 32°F (0°C). An average low-temperature of 21.6°F (-5.8°C) is expected in Harvard during December.Humidity
The average relative humidity in December is 83%.Rainfall
The month with the least rainfall is December, when the rain falls for 7.9 days and typically collects 1.3" (33mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In December, it is snowing for 11.6 days. Throughout December, 2.95" (75mm) of snow is accumulated. Throughout the year, there are 54.4 snowfall days, and 16.93" (430mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 6min of daylight.On the first day of the month, sunrise is at 7:04 am and sunset at 4:22 pm. On the last day of December, sunrise is at 7:23 am and sunset at 4:31 pm CST.
Sunshine
In Harvard, the average sunshine in December is 3.8h.UV index
January and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for average individuals.Note: An average UV index of 1 in December transforms into this advice:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. Around midday, solar radiation is most harmful; hence, exposure should be limited. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades. Be prepared! The intensity of the Sun's UV radiation can be amplified nearly double due to snow reflection.
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 in Harvard?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December in Harvard?
When is the sunrise / sunset in December?
How long on average sun shines in December?
What are the months with the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Harvard, IL
- Average high temperature in December: 32°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (25.3°F).
- Average low temperature in December: 21.6°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (13.3°F).
Average pressure in December
Harvard, 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
Harvard, IL
- Average wind speed in December: 9.1mph
The windiest month (with the highest average wind speed) is April (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in December
Harvard, IL
- Average humidity in December: 83%
The month with the highest relative humidity is January (87%).
The months with the lowest relative humidity are April and October (77%).
Average rainfall in December
Harvard, IL
- Average rainfall in December: 1.3"
The wettest month (with the highest rainfall) is June (3.58").
The driest month (with the least rainfall) is December (1.3").
Average rainfall days in December
Harvard, IL
- Average rainfall days in December: 7.9 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is January (4.9 days).
Average snowfall in December
Harvard, IL
- Average snowfall in December: 2.95"
The month with the highest snowfall is January (4.41").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Harvard, IL
- Average snowfall days in December: 11.6 days
The month with the highest number of snowfall days is January (14.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Harvard, 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 6min).
- Average sunshine in December: 3h and 5min
The month with the most sunshine is July (Average sunshine: 9h and 36min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in December
Harvard, IL
- Average sunshine days in December: 14.4 days
The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is May (9.7 days).
Average UV index in December
Harvard, IL
- Average UV index in December: 1
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Harvard, IL
- Average cloud cover in December: 61
The month with the most cloud cover is January (Cloud cover 64).
The month with the least cloud cover is September (Cloud cover 35).
Average visibility in December
Harvard, IL
- Average visibility in December: 5mi
The months with the highest visibility are March, April, May, June, October and November (6mi).
The months with the lowest visibility are January, February, July, August, September and December (5mi).
Harvard, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location