December weather forecastHarwood Heights, IL
December
Weather in December
The first month of the winter, December, is also an icy month in Harwood Heights, Illinois, with an average temperature varying between 26.1°F (-3.3°C) and 35.1°F (1.7°C).Temperature
The onset of December brings a small change in high-temperatures, falling from a chilly 45.7°F (7.6°C) in November to a wintry 35.1°F (1.7°C). During the December nights, Harwood Heights's temperature maintains an average close to the daytime highs, settling at a subzero cold 26.1°F (-3.3°C).Humidity
In December, the average relative humidity is 80%.Rainfall
The month with the least rainfall is December, when the rain falls for 4.5 days and typically collects 0.31" (8mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Harwood Heights, during December, snow falls for 5.8 days and regularly aggregates up to 0.16" (4mm) of snow. In Harwood Heights, during the entire year, snow falls for 28.5 days and aggregates up to 3.07" (78mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:00 am and sunset at 4:20 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 4:30 pm CST.
Sunshine
In December, the average sunshine is 3.9h.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 1. A UV Index estimate of 2, and below, represents a minimal health hazard from exposure to the Sun's UV radiation for average individuals.Note: The daily high UV index of 1 in December translates into this advice:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. The Sun's harshest UV rays are around midday; it's wise to seek shade and limit time outdoors. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Harwood Heights, IL
- Average high temperature in December: 35.1°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in December: 26.1°F
The month with the highest average low temperature is July (67.5°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in December
Harwood Heights, 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
Harwood Heights, IL
- Average wind speed in December: 10.4mph
The windiest month (with the highest average wind speed) is January (11.1mph).
The calmest month (with the lowest average wind speed) is August (7mph).
Average humidity in December
Harwood Heights, IL
- Average humidity in December: 80%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Harwood Heights, IL
- Average rainfall in December: 0.31"
The wettest month (with the highest rainfall) is May (1.06").
The driest month (with the least rainfall) is December (0.31").
Average rainfall days in December
Harwood Heights, IL
- Average rainfall days in December: 4.5 days
The month with the highest number of rainy days is May (12.3 days).
The month with the least rainy days is February (2.8 days).
Average snowfall in December
Harwood Heights, IL
- Average snowfall in December: 0.16"
The month with the highest snowfall is February (0.98").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Harwood Heights, IL
- Average snowfall days in December: 5.8 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Harwood Heights, IL
- Average daylight in December: 9h and 12min
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: 3h and 54min
The months with the most sunshine are July and August (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Harwood Heights, IL
- Average sunshine days in December: 23.3 days
The month with the most sunshine days is December (23.3 days).
The month with the least sunshine days is June (14.7 days).
Average UV index in December
Harwood Heights, IL
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Harwood Heights, IL
- Average cloud cover in December: 59
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are July and August (Cloud cover 28).
Average visibility in December
Harwood Heights, 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).
