December weather forecastGrand River, IA
December
Weather in December
The first month of the winter, December, is also a wintry month in Grand River, Iowa, with temperature in the range of an average high of 35.6°F (2°C) and an average low of 23.4°F (-4.8°C).Temperature
The arrival of December corresponds with a shift in temperature, down from a frosty 48.6°F (9.2°C) in November to a cold 35.6°F (2°C). During December, Grand River experiences an average low-temperature of 23.4°F (-4.8°C) at night.Humidity
In December, the average relative humidity is 79%.Rainfall
The months with the least rainfall are January and December Rain falls for 5.7 days and accumulates 0.67" (17mm) of rain.Snowfall
Months with snowfall are January through May, October through December. In Grand River, during December, snow falls for 5.9 days and regularly aggregates up to 1.14" (29mm) of snow. Throughout the year, there are 30.2 snowfall days, and 10.16" (258mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:21 am and sunset at 4:48 pm. On the last day of December, sunrise is at 7:40 am and sunset at 4:58 pm CST.
Sunshine
In Grand River, the average sunshine in December is 4.9h.UV index
In December, the average daily maximum UV index is 2. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: An average maximum UV index of 2 in December leads to these recommendations:
Apart from children, who require continuous protection, most can endure sun exposure for up to an hour without experiencing burns. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades. 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
Grand River, IA
- Average high temperature in December: 35.6°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (30.6°F).
- Average low temperature in December: 23.4°F
The month with the highest average low temperature is July (66°F).
The coldest month (with the lowest average low temperature) is January (16.9°F).
Average pressure in December
Grand River, IA
- Average pressure in December: 30.12"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in December
Grand River, IA
- Average wind speed in December: 9.9mph
The windiest months (with the highest average wind speed) are January, February and March (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.9mph).
Average humidity in December
Grand River, IA
- Average humidity in December: 79%
The month with the highest relative humidity is June (83%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Grand River, IA
- Average rainfall in December: 0.67"
The wettest month (with the highest rainfall) is June (3.43").
The driest months (with the least rainfall) are January and December (0.67").
Average rainfall days in December
Grand River, IA
- Average rainfall days in December: 5.7 days
The month with the highest number of rainy days is June (17.3 days).
The month with the least rainy days is January (4.8 days).
Average snowfall in December
Grand River, IA
- Average snowfall in December: 1.14"
The month with the highest snowfall is January (2.72").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Grand River, IA
- Average snowfall days in December: 5.9 days
The month with the highest number of snowfall days is January (8.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grand River, IA
- 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 54min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in December
Grand River, IA
- Average sunshine days in December: 20.3 days
The month with the most sunshine days is December (20.3 days).
The month with the least sunshine days is June (8.9 days).
Average UV index in December
Grand River, IA
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in December
Grand River, IA
- Average cloud cover in December: 47
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 28).
Average visibility in December
Grand River, IA
- 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).
