December weather forecastSpring Valley, IL
December
Weather in December
The first month of the winter, December, is still a cold month in Spring Valley, Illinois, with an average temperature varying between 24.4°F (-4.2°C) and 34.7°F (1.5°C).Temperature
Onset of December comes with a temperature decline, the average high falling from a frosty 46.8°F (8.2°C) in November to an icy 34.7°F (1.5°C). In the month of December, Spring Valley's average low-temperature falls to a freezing cold 24.4°F (-4.2°C).Humidity
In December, the average relative humidity is 82%.Rainfall
The months with the least rainfall are January and December Rain falls for 7.5 days and accumulates 1.61" (41mm) of rain.Snowfall
January through April, October through December are months with snowfall. In December, it is snowing for 8 days. Throughout December, 2.6" (66mm) of snow is accumulated. In Spring Valley, during the entire year, snow falls for 39.5 days and aggregates up to 15.31" (389mm) of snow.Daylight
The month with the shortest days in Spring Valley is December, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:03 am and sunset at 4:28 pm. On the last day of December, sunrise is at 7:22 am and sunset at 4:37 pm CST.
Sunshine
The average sunshine in December is 4.2h.UV index
The months with the lowest UV index are January and December, 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 radiation for the ordinary person.Note: In December, a daily maximum UV index of 1 leads to the following instructions:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. To cut down UV radiation exposure by about half, sport a wide-brim hat. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Spring Valley, IL
- Average high temperature in December: 34.7°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 (28.9°F).
- Average low temperature in December: 24.4°F
The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (16.9°F).
Average pressure in December
Spring Valley, IL
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Spring Valley, IL
- Average wind speed in December: 9.6mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in December
Spring Valley, IL
- Average humidity in December: 82%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Spring Valley, IL
- Average rainfall in December: 1.61"
The wettest month (with the highest rainfall) is May (4.69").
The driest months (with the least rainfall) are January and December (1.61").
Average rainfall days in December
Spring Valley, IL
- Average rainfall days in December: 7.5 days
The month with the highest number of rainy days is May (18.9 days).
The month with the least rainy days is January (5.9 days).
Average snowfall in December
Spring Valley, IL
- Average snowfall in December: 2.6"
The month with the highest snowfall is January (4.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Spring Valley, IL
- Average snowfall days in December: 8 days
The month with the highest number of snowfall days is January (11.9 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Spring Valley, IL
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 4h and 12min
The months with the most sunshine are June, July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in December
Spring Valley, IL
- Average sunshine days in December: 16.2 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is April (10.2 days).
Average UV index in December
Spring Valley, 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
Spring Valley, IL
- Average cloud cover in December: 55
The month with the most cloud cover is January (Cloud cover 59).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility in December
Spring Valley, IL
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).
