December weather forecastAltona, IL
December
Weather in December
The first month of the winter, December, is also an icy month in Altona, Illinois, with an average temperature fluctuating between 24.1°F (-4.4°C) and 34.7°F (1.5°C).Temperature
Start of December brings a shift in the average high-temperature, falling from November's frosty 46.9°F (8.3°C) to a cold 34.7°F (1.5°C). During December nights, Altona witnesses a consistent average temperature of 24.1°F (-4.4°C).Humidity
In Altona, the average relative humidity in December is 82%.Rainfall
December is the month with the least rainfall. Rain falls for 6.5 days and accumulates 0.71" (18mm) of precipitation.Snowfall
Months with snowfall in Altona are January through April, October through December. In Altona, in December, snow falls for 7.4 days, with typically accumulated 0.91" (23mm) of snow. Throughout the year, in Altona, there are 35.5 snowfall days, and 7.95" (202mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:07 am and sunset at 4:32 pm. On the last day of December, in Altona, sunrise is at 7:25 am and sunset at 4:42 pm CST.
Sunshine
In Altona, the average sunshine in December is 4.3h.UV index
The average daily maximum UV index in December is 2. A UV Index of 2, and less, symbolizes a low threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In December, the UV index of 2 transforms into the following advice:
Apart from children, who require continuous protection, most can endure sun exposure for up to an hour without experiencing burns. When the Sun is at its strongest around midday, find shade and limit exposure. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Take precaution! The reflection from snow can almost double the UV radiation of the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Altona, IL
- Average high temperature in December: 34.7°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (28.2°F).
- Average low temperature in December: 24.1°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (16.5°F).
Average pressure in December
Altona, IL
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Altona, IL
- Average wind speed in December: 9.9mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in December
Altona, IL
- Average humidity in December: 82%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Altona, IL
- Average rainfall in December: 0.71"
The wettest month (with the highest rainfall) is May (2.76").
The driest month (with the least rainfall) is December (0.71").
Average rainfall days in December
Altona, IL
- Average rainfall days in December: 6.5 days
The month with the highest number of rainy days is May (16.5 days).
The month with the least rainy days is January (4 days).
Average snowfall in December
Altona, IL
- Average snowfall in December: 0.91"
The month with the highest snowfall is January (2.17").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Altona, IL
- Average snowfall days in December: 7.4 days
The month with the highest number of snowfall days is January (10.5 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
Altona, IL
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 4h and 18min
The months with the most sunshine are June and July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Altona, IL
- Average sunshine days in December: 19.2 days
The month with the most sunshine days is November (19.7 days).
The month with the least sunshine days is July (11.2 days).
Average UV index in December
Altona, IL
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in December
Altona, IL
- Average cloud cover in December: 54
The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 29).
Average visibility in December
Altona, IL
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
