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 indicates a noticeable reduction in the average high-temperature, moving down from a chilly 45.5°F (7.5°C) in November to a subzero cold 29.1°F (-1.6°C). Iona witnesses a consistent average low-temperature of 16.9°F (-8.4°C) throughout December.Humidity
The average relative humidity in December in Iona is 82%.Rainfall
In December, the rain falls for 3.9 days. Throughout December, 0.94" (24mm) of precipitation is accumulated. In Iona, during the entire year, the rain falls for 107.6 days and collects up to 17.83" (453mm) of precipitation.Snowfall
January through April, October through December are months with snowfall in Iona. In Iona, in December, during 9.6 snowfall days, 3.07" (78mm) of snow is typically accumulated. In Iona, during the entire year, snow falls for 50.9 days and aggregates up to 17.87" (454mm) of snow.Daylight
The month with the shortest days in Iona is December, with an average of 9h and 0min of daylight.On the first day of the month, sunrise is at 7:51 am and sunset at 5:02 pm. On the last day of December, sunrise is at 8:10 am and sunset at 5:11 pm CST.
Sunshine
In Iona, the average sunshine in December is 4.9h.UV index
In December, the average daily maximum UV index in Iona is 2. A UV Index estimate of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for average individuals.Note: The daily high UV index of 2 in December translates into this advice:
Children must always have sun protection, unlike most people, who can tolerate up to an hour in the sun without any burns. When the Sun is at its strongest around midday, find shade and limit exposure. To cut down UV radiation exposure by about half, sport a wide-brim hat. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Frequently asked questions
How cold is it in Iona in December?
What is the average humidity in December in Iona?
How much does it rain in Iona in December?
How many days does it snow in December in Iona?
What is the month with the shortest days in Iona?
How many hours of daylight does Iona have in December?
When are sunrise and sunset in December in Iona?
How long on average sun shines in December in Iona?
What is the UV index intensity in December in Iona?
Average temperature in December
Iona, SD
- Average high temperature in December: 29.1°F
The warmest month (with the highest average high temperature) is July (88°F).
The month with the lowest average high temperature is January (26.1°F).
- Average low temperature in December: 16.9°F
The month with the highest average low temperature is July (66.2°F).
The coldest month (with the lowest average low temperature) is January (12.6°F).
Average pressure in December
Iona, SD
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).
Average wind speed in December
Iona, SD
- Average wind speed in December: 10mph
The windiest month (with the highest average wind speed) is April (11.3mph).
The calmest month (with the lowest average wind speed) is August (9.1mph).
Average humidity in December
Iona, SD
- Average humidity in December: 82%
The month with the highest relative humidity is January (86%).
The month with the lowest relative humidity is September (58%).
Average rainfall in December
Iona, SD
- Average rainfall in December: 0.94"
The wettest month (with the highest rainfall) is June (3.03").
The driest month (with the least rainfall) is November (0.55").
Average rainfall days in December
Iona, SD
- Average rainfall days in December: 3.9 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is February (3.3 days).
Average snowfall in December
Iona, SD
- Average snowfall in December: 3.07"
The month with the highest snowfall is February (3.66").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Iona, SD
- Average snowfall days in December: 9.6 days
The months with the highest number of snowfall days are January and February (11.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Iona, SD
- Average daylight in December: 9h and 0min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in December: 4h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in December
Iona, SD
- Average sunshine days in December: 19.5 days
The month with the most sunshine days is November (20.7 days).
The month with the least sunshine days is April (11.8 days).
Average UV index in December
Iona, SD
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is February (UV index 1).
Average cloud cover in December
Iona, SD
- Average cloud cover in December: 47
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 20).
Average visibility in December
Iona, SD
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Iona, South Dakota, USA
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