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
Forreston's December weather shows a moderate shift in high-temperatures, falling from November's chilly 44.6°F (7°C) to an icy 32.4°F (0.2°C). Forreston observes an average nighttime temperature of 22.3°F (-5.4°C) during December.Humidity
In December, the average relative humidity in Forreston is 83%.Rainfall
February and December are months with the least rain in Forreston when the rain falls for 7.5 days and typically aggregates up to 1.06" (27mm) of rain.Snowfall
Months with snowfall in Forreston are January through April, October through December. In Forreston, Illinois, in December, snow falls for 9.9 days, with typically accumulated 2.09" (53mm) of snow. In Forreston, during the entire year, snow falls for 45.5 days and aggregates up to 13.15" (334mm) of snow.Daylight
The month with the shortest days in Forreston is December, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 7:07 am and sunset at 4:27 pm. On the last day of December, in Forreston, sunrise is at 7:26 am and sunset at 4:36 pm CST.
Sunshine
In December, the average sunshine in Forreston is 4h.UV index
The months with the lowest UV index in Forreston are January and December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for the average person.Note: A typical high UV index of 1 in December suggests the following recommendations:
Long-term sun exposure is typically not a concern for most. However, those with sensitive skin, infants, and children must always have protection. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December in Forreston?
What is the average humidity in December in Forreston?
What is the driest month in Forreston?
How many days does it rain in December in Forreston?
How much does it snow in Forreston in December?
What is the month with the shortest days in Forreston?
What is the average length of the day in December in Forreston?
When are sunrise and sunset in December in Forreston?
How long on average sun shines in December in Forreston?
When is the lowest UV index in Forreston?
How high is the UV index in December in Forreston?
Average temperature in December
Forreston, IL
- Average high temperature in December: 32.4°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 (26.1°F).
- Average low temperature in December: 22.3°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (13.5°F).
Average pressure in December
Forreston, 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
Forreston, IL
- Average wind speed in December: 9.4mph
The windiest month (with the highest average wind speed) is April (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.5mph).
Average humidity in December
Forreston, 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 (75%).
Average rainfall in December
Forreston, IL
- Average rainfall in December: 1.06"
The wettest month (with the highest rainfall) is June (3.39").
The driest months (with the least rainfall) are February and December (1.06").
Average rainfall days in December
Forreston, IL
- Average rainfall days in December: 7.5 days
The month with the highest number of rainy days is May (18.3 days).
The month with the least rainy days is February (5 days).
Average snowfall in December
Forreston, IL
- Average snowfall in December: 2.09"
The month with the highest snowfall is January (3.54").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Forreston, IL
- Average snowfall days in December: 9.9 days
The month with the highest number of snowfall days is January (12.4 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
Forreston, 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 0min
The month with the most sunshine is July (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in December
Forreston, IL
- Average sunshine days in December: 16.3 days
The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is June (9.7 days).
Average UV index in December
Forreston, 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
Forreston, IL
- Average cloud cover in December: 59
The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is September (Cloud cover 33).
Average visibility in December
Forreston, IL
- Average visibility in December: 6mi
The months with the highest visibility are March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, February, July and August (5mi).
Forreston, Illinois, USA
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