Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December brings a decrease in the average high-temperature, shifting from a frosty 43.9°F (6.6°C) in November to a subzero cold 31.5°F (-0.3°C). Rockdale observes an average nighttime low-temperature of 21°F (-6.1°C) during the month of December.Humidity
In Rockdale, the average relative humidity in December is 82%.Rainfall
In Rockdale, during December, the rain falls for 6.3 days and regularly aggregates up to 1.38" (35mm) of precipitation. Throughout the year, there are 135.3 rainfall days, and 27.4" (696mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, October through December. In Rockdale, in December, snow falls for 9 days, with typically accumulated 2.68" (68mm) of snow. Throughout the year, there are 43.9 snowfall days, and 17.09" (434mm) of snow is accumulated.Daylight
With an average of 9h and 6min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:13 am and sunset at 4:30 pm. On the last day of December, sunrise is at 7:32 am and sunset at 4:39 pm CST.
Sunshine
In Rockdale, the average sunshine in December is 4h.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 rays for the ordinary person.Note: In December, the maximum UV index of 1 suggests this advice:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in December?
What is the average humidity in December?
How many days does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When is the sunrise / sunset in December?
How many hours of sunshine does Rockdale have in December?
What are the months with the lowest UV index?
What is the UV index reading in December?
Average temperature in December
Rockdale, IA
- Average high temperature in December: 31.5°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (25°F).
- Average low temperature in December: 21°F
The month with the highest average low temperature is July (62.8°F).
The coldest month (with the lowest average low temperature) is January (12.4°F).
Average pressure in December
Rockdale, 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
Rockdale, IA
- Average wind speed in December: 9.8mph
The windiest month (with the highest average wind speed) is April (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.8mph).
Average humidity in December
Rockdale, IA
- Average humidity in December: 82%
The months with the highest relative humidity are January and February (87%).
The month with the lowest relative humidity is October (76%).
Average rainfall in December
Rockdale, IA
- Average rainfall in December: 1.38"
The wettest months (with the highest rainfall) are May and June (3.7").
The driest months (with the least rainfall) are January and February (1.14").
Average rainfall days in December
Rockdale, IA
- Average rainfall days in December: 6.3 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (4.4 days).
Average snowfall in December
Rockdale, IA
- Average snowfall in December: 2.68"
The month with the highest snowfall is January (4.88").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Rockdale, IA
- Average snowfall days in December: 9 days
The month with the highest number of snowfall days is January (12.8 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
Rockdale, IA
- Average daylight in December: 9h and 1min
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 6min).
- Average sunshine in December: 4h and 0min
The months with the most sunshine are July and August (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in December
Rockdale, IA
- Average sunshine days in December: 17.5 days
The months with the most sunshine days are November and December (17.5 days).
The month with the least sunshine days is June (10.3 days).
Average UV index in December
Rockdale, IA
- Average UV index in December: 1
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January, November and December (UV index 1).
Average cloud cover in December
Rockdale, IA
- Average cloud cover in December: 59
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in December
Rockdale, 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).
Rockdale, Iowa, USA
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