December weather forecastGreen Island, IA
December
Weather in December
The first month of the winter, December, is also an icy month in Green Island, Iowa, with temperature in the range of an average high of 32°F (0°C) and an average low of 21.6°F (-5.8°C).Temperature
With December's onset, the average high-temperature recedes from November's frosty 44.8°F (7.1°C) to an icy 32°F (0°C). Green Island records an average low of 21.6°F (-5.8°C) throughout the nights in December.Humidity
The average relative humidity in December is 82%.Rainfall
In Green Island, Iowa, in December, it is raining for 6.5 days, with typically 1.5" (38mm) of accumulated precipitation. Throughout the year, there are 145.6 rainfall days, and 28.9" (734mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall. In Green Island, during December, snow falls for 8.7 days and regularly aggregates up to 2.72" (69mm) of snow. In Green Island, during the entire year, snow falls for 40.1 days and aggregates up to 16.61" (422mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:10 am and sunset at 4:30 pm. On the last day of the month, sunrise is at 7:29 am and sunset at 4:39 pm CST.
Sunshine
In Green Island, the average sunshine in December is 4.2h.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a low threat to health from exposure to the Sun's UV radiation for the average person.Note: In December, a daily maximum UV index of 1 leads to the following instructions:
Babies, children, and individuals with sensitive skin should always have protection against extended sun exposure. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Be aware! The reflective nature of snow can magnify the Sun's UV radiation almost twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Green Island, IA
- Average high temperature in December: 32°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is January (25.7°F).
- Average low temperature in December: 21.6°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).
Average pressure in December
Green Island, IA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in December
Green Island, IA
- Average wind speed in December: 9.6mph
The windiest month (with the highest average wind speed) is April (10.3mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in December
Green Island, IA
- Average humidity in December: 82%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (75%).
Average rainfall in December
Green Island, IA
- Average rainfall in December: 1.5"
The wettest month (with the highest rainfall) is May (4.13").
The driest month (with the least rainfall) is January (1.22").
Average rainfall days in December
Green Island, IA
- Average rainfall days in December: 6.5 days
The month with the highest number of rainy days is May (19.8 days).
The month with the least rainy days is February (4.5 days).
Average snowfall in December
Green Island, IA
- Average snowfall in December: 2.72"
The month with the highest snowfall is January (4.61").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Green Island, IA
- Average snowfall days in December: 8.7 days
The month with the highest number of snowfall days is January (10.6 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
Green Island, IA
- Average daylight in December: 9h and 12min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 4h and 12min
The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in December
Green Island, IA
- Average sunshine days in December: 17.1 days
The month with the most sunshine days is November (19 days).
The month with the least sunshine days is May (9.5 days).
Average UV index in December
Green Island, IA
- 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 and December (UV index 1).
Average cloud cover in December
Green Island, IA
- Average cloud cover in December: 57
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are August and September (Cloud cover 32).
Average visibility in December
Green Island, IA
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, August, September, October, November and December (6mi).
The months with the lowest visibility are January and July (5mi).





