December weather forecastGrayville, IL
December
Weather in December
The first month of the winter, December, is also a frosty month in Grayville, Illinois, with temperature in the range of an average high of 43.5°F (6.4°C) and an average low of 31.5°F (-0.3°C).Temperature
December's arrival comes with a decrease in the average high-temperature, moving from a cool 53.1°F (11.7°C) in November to a frosty 43.5°F (6.4°C). December is noted for a mean low-temperature of 31.5°F (-0.3°C).Humidity
In Grayville, the average relative humidity in December is 78%.Rainfall
In Grayville, in December, it is raining for 11 days, with typically 3.03" (77mm) of accumulated precipitation. Throughout the year, there are 167.7 rainfall days, and 38.23" (971mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In Grayville, in December, snow falls for 4.5 days, with typically accumulated 1.22" (31mm) of snow. In Grayville, during the entire year, snow falls for 20.5 days and aggregates up to 6.06" (154mm) of snow.Daylight
December has the shortest days of the year in Grayville, Illinois, with an average of 9h and 36min of daylight.On the first day of December, sunrise is at 6:50 am and sunset at 4:32 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 4:42 pm CST.
Sunshine
The average sunshine in December in Grayville is 4.6h.UV index
The months with the lowest UV index in Grayville, Illinois, are January, February, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV rays for ordinary individuals.Note: In December, the maximum UV index of 2 suggests these recommendations:
Prolonged exposure to sunlight rarely troubles the majority, but constant protection is vital for babies, children, and fair-skinned people. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Grayville, IL
- Average high temperature in December: 43.5°F
The warmest month (with the highest average high temperature) is July (85.5°F).
The month with the lowest average high temperature is January (38.1°F).
- Average low temperature in December: 31.5°F
The month with the highest average low temperature is July (68°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in December
Grayville, 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
Grayville, IL
- Average wind speed in December: 9.4mph
The windiest months (with the highest average wind speed) are January and February (10.1mph).
The calmest month (with the lowest average wind speed) is July (5.9mph).
Average humidity in December
Grayville, IL
- Average humidity in December: 78%
The month with the highest relative humidity is July (80%).
The month with the lowest relative humidity is October (69%).
Average rainfall in December
Grayville, IL
- Average rainfall in December: 3.03"
The wettest month (with the highest rainfall) is April (5.2").
The driest month (with the least rainfall) is September (1.97").
Average rainfall days in December
Grayville, IL
- Average rainfall days in December: 11 days
The month with the highest number of rainy days is May (19.6 days).
The month with the least rainy days is January (9.8 days).
Average snowfall in December
Grayville, IL
- Average snowfall in December: 1.22"
The month with the highest snowfall is February (1.54").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Grayville, IL
- Average snowfall days in December: 4.5 days
The month with the highest number of snowfall days is January (6.6 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
Grayville, IL
- Average daylight in December: 9h and 36min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 4h and 36min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days in December
Grayville, IL
- Average sunshine days in December: 16.3 days
The month with the most sunshine days is October (18.2 days).
The month with the least sunshine days is May (8.8 days).
Average UV index in December
Grayville, 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, November and December (UV index 2).
Average cloud cover in December
Grayville, IL
- Average cloud cover in December: 51
The month with the most cloud cover is January (Cloud cover 52).
The month with the least cloud cover is June (Cloud cover 27).
Average visibility in December
Grayville, 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).
