December weather forecastRiver Grove, IL
December
Weather in December
The first month of the winter, December, is also a wintry month in River Grove, Illinois, with temperature in the range of an average low of 26.6°F (-3°C) and an average high of 35.1°F (1.7°C).Temperature
As River Grove enters December, the average high-temperature decreases from the a frosty 45.9°F (7.7°C) of November to a wintry 35.1°F (1.7°C). A mean low-temperature of 26.6°F (-3°C) is a distinguishing feature of December in River Grove, indicating a slight dip from daytime highs.Humidity
In December, the average relative humidity in River Grove is 80%.Rainfall
The month with the least rainfall is December, when the rain falls for 8.2 days and typically collects 1.57" (40mm) of precipitation.Snowfall
Months with snowfall in River Grove are January through May, October through December. In River Grove, Illinois, during December, snow falls for 8.3 days and regularly aggregates up to 2.52" (64mm) of snow. In River Grove, during the entire year, snow falls for 40.3 days and aggregates up to 16.81" (427mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:00 am and sunset at 4:21 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 4:30 pm CST.
Sunshine
The average sunshine in December is 4.1h.UV index
The months with the lowest UV index in River Grove are January and December, with an average maximum UV index of 1. A UV Index value of 2, and less, symbolizes a low health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In December, a regular UV index of 1 translates into these guidelines:
Sun exposure does not present considerable issues for many, yet infants, fair-skinned people, and children necessitate constant protection. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Opt for tightly woven and loose clothing to enhance protection from the Sun. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
River Grove, 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 (28.9°F).
- Average low temperature in December: 26.6°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 (19.4°F).
Average pressure in December
River Grove, 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
River Grove, IL
- Average wind speed in December: 10.4mph
The windiest month (with the highest average wind speed) is January (11.1mph).
The calmest months (with the lowest average wind speed) are July and August (7mph).
Average humidity in December
River Grove, 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
River Grove, IL
- Average rainfall in December: 1.57"
The wettest month (with the highest rainfall) is May (4.49").
The driest month (with the least rainfall) is December (1.57").
Average rainfall days in December
River Grove, IL
- Average rainfall days in December: 8.2 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is February (5.1 days).
Average snowfall in December
River Grove, IL
- Average snowfall in December: 2.52"
The month with the highest snowfall is February (4.69").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
River Grove, IL
- Average snowfall days in December: 8.3 days
The month with the highest number of snowfall days is January (10.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
River Grove, 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: 4h and 6min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
River Grove, IL
- Average sunshine days in December: 16.7 days
The month with the most sunshine days is December (16.7 days).
The month with the least sunshine days is July (9.9 days).
Average UV index in December
River Grove, 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
River Grove, IL
- Average cloud cover in December: 58
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
River Grove, 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).
