December weather forecastHartsville, IL
December
Weather in December
December, the first month of the winter in Hartsville, is still a chilly month, with an average temperature fluctuating between 44.1°F (6.7°C) and 32.4°F (0.2°C).Temperature
December's onset brings a reduction in the average high-temperature, from a fresh 53.8°F (12.1°C) in November to a frosty 44.1°F (6.7°C). During the month of December, Hartsville experiences a steady low-temperature average of 32.4°F (0.2°C).Humidity
The average relative humidity in December in Hartsville, Illinois, is 78%.Rainfall
In December, in Hartsville, the rain falls for 10.3 days. Throughout December, 2.8" (71mm) of precipitation is accumulated. Throughout the year, in Hartsville, there are 158.7 rainfall days, and 36.1" (917mm) of precipitation is accumulated.Snowfall
Months with snowfall in Hartsville are January through April, November and December. In Hartsville, in December, snow falls for 3.5 days, with typically accumulated 1.18" (30mm) of snow. In Hartsville, during the entire year, snow falls for 17.5 days and aggregates up to 6.5" (165mm) of snow.Daylight
The month with the shortest days in Hartsville is December, with an average of 9h and 36min of daylight.On the first day of December in Hartsville, sunrise is at 6:50 am and sunset at 4:35 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 4:46 pm CST.
Sunshine
With an average of 4.5h of sunshine, December has the least sunshine of the year in Hartsville.UV index
The months with the lowest UV index are January, February and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low health risk from unprotected exposure to Sun's UV rays for average individuals.Note: An average maximum UV index of 2 in December leads to these recommendations:
Despite the majority tolerating prolonged sun exposure, those with sensitive skin, infants, and children demand continual protection. The Sun's harshest UV rays are around midday; it's wise to seek shade and limit time outdoors. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Be cautious! The UV radiation from the Sun can be magnified almost twofold by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Hartsville, IL
- Average high temperature in December: 44.1°F
The warmest month (with the highest average high temperature) is July (87.3°F).
The month with the lowest average high temperature is January (39.7°F).
- Average low temperature in December: 32.4°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 (26.2°F).
Average pressure in December
Hartsville, 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
Hartsville, IL
- Average wind speed in December: 8.8mph
The windiest months (with the highest average wind speed) are January and February (9.4mph).
The calmest months (with the lowest average wind speed) are July and August (5.8mph).
Average humidity in December
Hartsville, IL
- Average humidity in December: 78%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in December
Hartsville, IL
- Average rainfall in December: 2.8"
The wettest month (with the highest rainfall) is April (4.8").
The driest month (with the least rainfall) is September (1.61").
Average rainfall days in December
Hartsville, IL
- Average rainfall days in December: 10.3 days
The month with the highest number of rainy days is May (18.5 days).
The month with the least rainy days is November (9.7 days).
Average snowfall in December
Hartsville, IL
- Average snowfall in December: 1.18"
The month with the highest snowfall is January (1.73").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Hartsville, IL
- Average snowfall days in December: 3.5 days
The month with the highest number of snowfall days is January (5.3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Hartsville, 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 30min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 4h and 30min).
Average sunshine days in December
Hartsville, IL
- Average sunshine days in December: 17 days
The month with the most sunshine days is October (19.5 days).
The month with the least sunshine days is May (9.9 days).
Average UV index in December
Hartsville, 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
Hartsville, IL
- Average cloud cover in December: 50
The months with the most cloud cover are January and February (Cloud cover 51).
The month with the least cloud cover is June (Cloud cover 28).
Average visibility in December
Hartsville, 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).
