December weather forecastSimpson, IL
December
Weather in December
The first month of the winter, December, is also a frosty month in Simpson, Illinois, with an average temperature ranging between max 44.8°F (7.1°C) and min 32.7°F (0.4°C).Temperature
The arrival of December corresponds with a reduction in the average high-temperature, down from November's cool 54.5°F (12.5°C) to a chilly 44.8°F (7.1°C). Simpson temperatures generally rest at a low of 32.7°F (0.4°C) during the December nights.Humidity
The average relative humidity in December is 78%.Rainfall
In Simpson, during December, the rain falls for 7.3 days and regularly aggregates up to 0.79" (20mm) of precipitation. Throughout the year, in Simpson, there are 118.3 rainfall days, and 13.03" (331mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through March, November and December. In December, in Simpson, it is snowing for 1.9 days. Throughout December, 0.12" (3mm) of snow is accumulated. Throughout the year, there are 11 snowfall days, and 1.57" (40mm) of snow is accumulated.Daylight
With an average of 9h and 36min of daylight, December has the shortest days of the year in Simpson.On the first day of December in Simpson, sunrise is at 6:51 am and sunset at 4:37 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 4:47 pm CST.
Sunshine
In Simpson, the average sunshine in December is 4.8h.UV index
January, February and December, with an average maximum UV index of 2, are months with the lowest UV index. 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: In December, the average maximum UV index of 2 translates into the following recommendations:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Warning! The reflection from snow can nearly magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Simpson, IL
- Average high temperature in December: 44.8°F
The warmest month (with the highest average high temperature) is July (88°F).
The month with the lowest average high temperature is January (40.1°F).
- Average low temperature in December: 32.7°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (27°F).
Average pressure in December
Simpson, IL
- Average pressure in December: 30.14"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Simpson, IL
- Average wind speed in December: 8.5mph
The windiest months (with the highest average wind speed) are January and February (9mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).
Average humidity in December
Simpson, IL
- Average humidity in December: 78%
The months with the highest relative humidity are March and May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Simpson, IL
- Average rainfall in December: 0.79"
The wettest month (with the highest rainfall) is June (1.5").
The driest month (with the least rainfall) is September (0.47").
Average rainfall days in December
Simpson, IL
- Average rainfall days in December: 7.3 days
The month with the highest number of rainy days is July (13.1 days).
The months with the least rainy days are January, February and December (7.3 days).
Average snowfall in December
Simpson, IL
- Average snowfall in December: 0.12"
The month with the highest snowfall is February (0.67").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Simpson, IL
- Average snowfall days in December: 1.9 days
The month with the highest number of snowfall days is January (3.3 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
Simpson, IL
- Average daylight in December: 9h and 36min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 4h and 48min
The months with the most sunshine are June and July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 36min).
Average sunshine days in December
Simpson, IL
- Average sunshine days in December: 21.2 days
The month with the most sunshine days is October (21.5 days).
The month with the least sunshine days is June (14.8 days).
Average UV index in December
Simpson, IL
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in December
Simpson, IL
- Average cloud cover in December: 49
The months with the most cloud cover are January and February (Cloud cover 51).
The month with the least cloud cover is September (Cloud cover 28).
Average visibility in December
Simpson, 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).
