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
In December, the meteorological conditions markedly change with the average high-temperature descending from a chilly 43.2°F (6.2°C) in November to a subzero cold 27.5°F (-2.5°C). Throughout December, Royal witnesses a consistent average low-temperature of 16.9°F (-8.4°C).Humidity
In December, the average relative humidity in Royal is 84%.Rainfall
In Royal, Iowa, during December, the rain falls for 4 days and regularly aggregates up to 0.83" (21mm) of precipitation. In Royal, during the entire year, the rain falls for 112.3 days and collects up to 15.31" (389mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Royal, during December, snow falls for 9.9 days and regularly aggregates up to 2.05" (52mm) of snow. Throughout the year, there are 45.5 snowfall days, and 11.14" (283mm) of snow is accumulated.Daylight
The month with the shortest days in Royal, Iowa, is December, with an average of 9h and 6min of daylight.On the first day of December in Royal, sunrise is at 7:33 am and sunset at 4:47 pm. On the last day of the month, sunrise is at 7:52 am and sunset at 4:56 pm CST.
Sunshine
The average sunshine in December in Royal, Iowa, is 4.4h.UV index
The average daily maximum UV index in December in Royal is 2. A UV Index estimate of 2, and below, represents a low threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: In December, a daily maximum UV index of 2 leads to the following instructions:
Many can withstand an hour in the sun without burning, yet children must always have protection against sunlight. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. During bright days, sunglasses that offer UVA and UVB defense are recommended. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.
Frequently asked questions
How cold is December in Royal?
What is the average humidity in December in Royal?
How many days does it rain in December in Royal?
How much does it snow in Royal in December?
What is the month with the shortest days in Royal?
How many hours of daylight does Royal have in December?
When is the sunrise / sunset in December in Royal?
How long on average sun shines in December in Royal?
What is the UV index intensity in December in Royal?
Average temperature in December
Royal, IA
- Average high temperature in December: 27.5°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (22.8°F).
- Average low temperature in December: 16.9°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (10.6°F).
Average pressure in December
Royal, 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 (29.87"Hg).
Average wind speed in December
Royal, IA
- Average wind speed in December: 10.7mph
The windiest months (with the highest average wind speed) are January and April (11.1mph).
The calmest month (with the lowest average wind speed) is July (7.6mph).
Average humidity in December
Royal, IA
- Average humidity in December: 84%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is October (68%).
Average rainfall in December
Royal, IA
- Average rainfall in December: 0.83"
The wettest month (with the highest rainfall) is June (2.44").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in December
Royal, IA
- Average rainfall days in December: 4 days
The month with the highest number of rainy days is May (15.5 days).
The month with the least rainy days is February (2.7 days).
Average snowfall in December
Royal, IA
- Average snowfall in December: 2.05"
The month with the highest snowfall is February (2.72").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Royal, IA
- Average snowfall days in December: 9.9 days
The month with the highest number of snowfall days is January (10.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Royal, IA
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 2min
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 0min).
Average sunshine days in December
Royal, IA
- Average sunshine days in December: 19.2 days
The month with the most sunshine days is November (20.1 days).
The month with the least sunshine days is June (10.8 days).
Average UV index in December
Royal, IA
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and February (UV index 1).
Average cloud cover in December
Royal, IA
- Average cloud cover in December: 55
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is July (Cloud cover 30).
Average visibility in December
Royal, 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).
Royal, Iowa, USA
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