December weather forecastRiverdale, IA
December
Weather in December
The first month of the winter, December, is still a cold month in Riverdale, Iowa, with an average temperature varying between 34.5°F (1.4°C) and 23.9°F (-4.5°C).Temperature
The shift from November to December corresponds with a decrease in the average high-temperature, down to a wintry 34.5°F (1.4°C) from a chilly 46.9°F (8.3°C). In December, the average low-temperature records at a subzero cold 23.9°F (-4.5°C) during the nights.Humidity
In Riverdale, Iowa, the average relative humidity in December is 81%.Rainfall
The month with the least rainfall is December, when the rain falls for 4.1 days and typically collects 0.35" (9mm) of precipitation.Snowfall
January through April, September through December are months with snowfall in Riverdale, Iowa. In December, it is snowing for 5 days. Throughout December, 0.39" (10mm) of snow is accumulated. Throughout the year, there are 24.5 snowfall days, and 4.09" (104mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 7:09 am and sunset at 4:32 pm. On the last day of December, in Riverdale, sunrise is at 7:28 am and sunset at 4:42 pm CST.
Sunshine
In Riverdale, the average sunshine in December is 4.2h.UV index
The average daily maximum UV index in December in Riverdale is 2. A UV Index of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum UV index of 2 during December translates into these guidelines:
Despite most people tolerating extended sun exposure, it is critical to always protect those with sensitive skin, infants, and children. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Riverdale, IA
- Average high temperature in December: 34.5°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.2°F).
- Average low temperature in December: 23.9°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (15.4°F).
Average pressure in December
Riverdale, IA
- 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
Riverdale, IA
- Average wind speed in December: 9.8mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.7mph).
Average humidity in December
Riverdale, IA
- Average humidity in December: 81%
The months with the highest relative humidity are January and July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Riverdale, IA
- Average rainfall in December: 0.35"
The wettest month (with the highest rainfall) is May (1.61").
The driest month (with the least rainfall) is December (0.35").
Average rainfall days in December
Riverdale, IA
- Average rainfall days in December: 4.1 days
The month with the highest number of rainy days is May (13.4 days).
The month with the least rainy days is January (3.2 days).
Average snowfall in December
Riverdale, IA
- Average snowfall in December: 0.39"
The month with the highest snowfall is January (1.26").
The months with the least snowfall are May, June, July and August (0").
Average snowfall days in December
Riverdale, IA
- Average snowfall days in December: 5 days
The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Riverdale, IA
- Average daylight in December: 9h and 12min
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 12min).
- Average sunshine in December: 4h and 12min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in December
Riverdale, IA
- Average sunshine days in December: 22.4 days
The month with the most sunshine days is December (22.4 days).
The month with the least sunshine days is June (14.4 days).
Average UV index in December
Riverdale, IA
- Average UV index in December: 2
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in December
Riverdale, IA
- Average cloud cover in December: 56
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility in December
Riverdale, 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).
