December weather forecastGrafton, WI
December
Weather in December
December, the first month of the winter in Grafton, is still a freezing cold month, with an average temperature varying between 31.5°F (-0.3°C) and 23.7°F (-4.6°C).Temperature
Onset of December comes with a temperature decline, the average high falling from a chilly 43°F (6.1°C) in November to a freezing cold 31.5°F (-0.3°C). In December, Grafton's nights cool slightly to a consistent average temperature of 23.7°F (-4.6°C).Humidity
In December, the average relative humidity is 83%.Rainfall
In Grafton, in December, during 5.7 rainfall days, 1.1" (28mm) of precipitation is typically accumulated. Throughout the year, there are 134.9 rainfall days, and 23.94" (608mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall. In December, it is snowing for 10.9 days. Throughout December, 3.03" (77mm) of snow is accumulated. In Grafton, during the entire year, snow falls for 51.1 days and aggregates up to 13.66" (347mm) of snow.Daylight
With an average of 9h and 0min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:05 am and sunset at 4:17 pm. On the last day of December, sunrise is at 7:24 am and sunset at 4:26 pm CST.
Sunshine
In Grafton, Wisconsin, the average sunshine in December is 3.9h.UV index
The months with the lowest UV index are January, November and December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation for average individuals.Note: In December, a daily maximum UV index of 1 leads to the following instructions:
Babies, children, and those with sensitive skin should always avoid extended periods in the sun. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. Opt for tightly woven and loose clothing to enhance protection from the Sun. Heed this! Snow reflection can almost augment the UV radiation of the sun by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Grafton, WI
- Average high temperature in December: 31.5°F
The warmest month (with the highest average high temperature) is July (76.1°F).
The month with the lowest average high temperature is January (25.5°F).
- Average low temperature in December: 23.7°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (15.8°F).
Average pressure in December
Grafton, WI
- Average pressure in December: 30.08"Hg
The months with the highest atmospheric pressure are January, February and March (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Grafton, WI
- Average wind speed in December: 11.4mph
The windiest month (with the highest average wind speed) is January (12.1mph).
The calmest month (with the lowest average wind speed) is July (7.5mph).
Average humidity in December
Grafton, WI
- Average humidity in December: 83%
The month with the highest relative humidity is January (86%).
The months with the lowest relative humidity are April, October and November (77%).
Average rainfall in December
Grafton, WI
- Average rainfall in December: 1.1"
The wettest month (with the highest rainfall) is July (2.99").
The driest month (with the least rainfall) is February (0.98").
Average rainfall days in December
Grafton, WI
- Average rainfall days in December: 5.7 days
The month with the highest number of rainy days is May (15.8 days).
The month with the least rainy days is February (3.8 days).
Average snowfall in December
Grafton, WI
- Average snowfall in December: 3.03"
The month with the highest snowfall is January (3.43").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Grafton, WI
- Average snowfall days in December: 10.9 days
The month with the highest number of snowfall days is January (12.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grafton, WI
- Average daylight in December: 9h and 0min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in December: 3h and 54min
The months with the most sunshine are July and August (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 3h and 36min).
Average sunshine days in December
Grafton, WI
- Average sunshine days in December: 16.4 days
The month with the most sunshine days is December (16.4 days).
The month with the least sunshine days is July (11.6 days).
Average UV index in December
Grafton, WI
- Average UV index in December: 1
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, November and December (UV index 1).
Average cloud cover in December
Grafton, WI
- Average cloud cover in December: 60
The month with the most cloud cover is January (Cloud cover 63).
The months with the least cloud cover are July and August (Cloud cover 28).
Average visibility in December
Grafton, WI
- 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).
