December weather forecastForrest, IL
December
Weather in December
December, the first month of the winter in Forrest, is still a cold month, with an average temperature varying between 26.1°F (-3.3°C) and 36.5°F (2.5°C).Temperature
As December commences, the average high-temperature shows a reduction, transitioning from a frosty 47.8°F (8.8°C) in November to an icy 36.5°F (2.5°C). An average low-temperature of 26.1°F (-3.3°C) is common during the nights of December.Humidity
In Forrest, the average relative humidity in December is 80%.Rainfall
In Forrest, during December, the rain falls for 6.9 days and regularly aggregates up to 0.87" (22mm) of precipitation. In Forrest, during the entire year, the rain falls for 130.5 days and collects up to 17.44" (443mm) of precipitation.Snowfall
January through April, October through December are months with snowfall. In Forrest, in December, snow falls for 6.1 days, with typically accumulated 1.1" (28mm) of snow. Throughout the year, there are 30.5 snowfall days, and 7.68" (195mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 6:59 am and sunset at 4:26 pm. On the last day of the month, sunrise is at 7:17 am and sunset at 4:36 pm CST.
Sunshine
The average sunshine in December is 4.3h.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 minimal health hazard from exposure to the Sun's UV rays for the ordinary person.Note: A daily high UV index of 1 in December leads to these guidelines:
Many can withstand an hour in the sun without burning, yet children must always have protection against sunlight. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Sun-related eye harm can be minimized with proper sunglasses offering UVA and UVB coverage. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Forrest, IL
- Average high temperature in December: 36.5°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in December: 26.1°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in December
Forrest, IL
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Forrest, IL
- Average wind speed in December: 10.2mph
The windiest month (with the highest average wind speed) is January (10.8mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in December
Forrest, IL
- Average humidity in December: 80%
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Forrest, IL
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is May (2.56").
The driest month (with the least rainfall) is January (0.79").
Average rainfall days in December
Forrest, IL
- Average rainfall days in December: 6.9 days
The month with the highest number of rainy days is May (17 days).
The months with the least rainy days are January and February (5 days).
Average snowfall in December
Forrest, IL
- Average snowfall in December: 1.1"
The month with the highest snowfall is January (2.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Forrest, IL
- Average snowfall days in December: 6.1 days
The month with the highest number of snowfall days is January (10.6 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
Forrest, IL
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 4h and 18min
The month with the most sunshine is June (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in December
Forrest, IL
- Average sunshine days in December: 18.9 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (11.4 days).
Average UV index in December
Forrest, IL
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Forrest, IL
- Average cloud cover in December: 56
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in December
Forrest, 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).





