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
Start of December brings a shift in the average high-temperature, falling from November's chilly 46.8°F (8.2°C) to a cold 33.3°F (0.7°C). In December, the nighttime temperature in Casey lowers to an average of 21.7°F (-5.7°C).Humidity
In Casey, the average relative humidity in December is 79%.Rainfall
In Casey, in December, during 4.1 rainfall days, 0.67" (17mm) of precipitation is typically accumulated. Throughout the year, in Casey, there are 117.3 rainfall days, and 19.09" (485mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Casey, in December, during 6 snowfall days, 1.3" (33mm) of snow is typically accumulated. Throughout the year, there are 31.7 snowfall days, and 9.29" (236mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:25 am and sunset at 4:49 pm. On the last day of the month, sunrise is at 7:44 am and sunset at 4:58 pm CST.
Sunshine
In December, the average sunshine is 4.8h.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 health risk from exposure to the Sun's UV rays for ordinary individuals.Note: In December, a daily UV index of 1 turns into the following recommendations:
Babies, children, and those with sensitive skin should always avoid extended periods in the sun. To protect against the Sun's most potent rays, avoid direct exposure around midday. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses. Remember this! The UV radiation of the Sun can be nearly doubled by the reflective properties of snow.
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 much does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December in Casey?
When are sunrise and sunset in December?
How many hours of sunshine does Casey have in December?
What are the months with the lowest UV index?
What is the UV index reading in December?
Average temperature in December
Casey, IA
- Average high temperature in December: 33.3°F
The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (28°F).
- Average low temperature in December: 21.7°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 (14.5°F).
Average pressure in December
Casey, 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 (29.88"Hg).
Average wind speed in December
Casey, IA
- Average wind speed in December: 10.3mph
The windiest months (with the highest average wind speed) are January and February (10.6mph).
The calmest month (with the lowest average wind speed) is July (7.1mph).
Average humidity in December
Casey, IA
- Average humidity in December: 79%
The months with the highest relative humidity are January and February (82%).
The month with the lowest relative humidity is October (70%).
Average rainfall in December
Casey, IA
- Average rainfall in December: 0.67"
The wettest month (with the highest rainfall) is June (3.11").
The driest month (with the least rainfall) is January (0.55").
Average rainfall days in December
Casey, IA
- Average rainfall days in December: 4.1 days
The month with the highest number of rainy days is May (16.4 days).
The month with the least rainy days is February (2.9 days).
Average snowfall in December
Casey, IA
- Average snowfall in December: 1.3"
The month with the highest snowfall is February (2.76").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Casey, IA
- Average snowfall days in December: 6 days
The month with the highest number of snowfall days is January (8.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Casey, IA
- Average daylight in December: 9h and 1min
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 5min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days in December
Casey, IA
- Average sunshine days in December: 22 days
The month with the most sunshine days is December (22 days).
The month with the least sunshine days is May (12.1 days).
Average UV index in December
Casey, IA
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Casey, IA
- Average cloud cover in December: 49
The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July and September (Cloud cover 30).
Average visibility in December
Casey, IA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, September, October, November and December (6mi).
The month with the lowest visibility is August (5mi).
Casey, Iowa, USA
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