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 comes with a drop in the average high-temperature, falling from November's frosty 49.6°F (9.8°C) to an icy 38.3°F (3.5°C). During the month of December, Mason City's nighttime temperature lowers to an average of 27.1°F (-2.7°C).Humidity
The average relative humidity in December in Mason City is 78%.Rainfall
The month with the least rainfall is December, when the rain falls for 8.1 days and typically collects 1.46" (37mm) of precipitation.Snowfall
January through April, October through December are months with snowfall in Mason City. In December, it is snowing for 6 days. Throughout December, 1.65" (42mm) of snow is accumulated. In Mason City, Illinois, during the entire year, snow falls for 31.9 days and aggregates up to 11.06" (281mm) of snow.Daylight
The month with the shortest days in Mason City is December, with an average of 9h and 24min of daylight.On the first day of December in Mason City, Illinois, sunrise is at 7:02 am and sunset at 4:33 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 4:43 pm CST.
Sunshine
In Mason City, the average sunshine in December is 4.6h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index estimate of 2, and below, represents a minimal health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum daily UV index of 2 in December converts into the following recommendations:
Most individuals face no major issues with lengthy exposure to the sun, but children, infants, and individuals with fair skin always require protection. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades. Foresee this! The reflection from snow can nearly double the intensity of UV radiation from the Sun.
Frequently asked questions
How cold is it in Mason City in December?
What is the average humidity in December in Mason City?
What is the driest month in Mason City?
How many days does it rain in December in Mason City?
How much does it snow in Mason City in December?
What is the month with the shortest days in Mason City?
How many hours of daylight does Mason City have in December?
What time are sunrise and sunset in December in Mason City?
How long on average sun shines in December in Mason City?
When is the lowest UV index in Mason City?
How high is the UV index in December in Mason City?
Average temperature in December
Mason City, IL
- Average high temperature in December: 38.3°F
The warmest month (with the highest average high temperature) is July (82.4°F).
The month with the lowest average high temperature is January (32°F).
- Average low temperature in December: 27.1°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (19.9°F).
Average pressure in December
Mason City, IL
- Average pressure in December: 30.12"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Mason City, IL
- Average wind speed in December: 9.7mph
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 (6.3mph).
Average humidity in December
Mason City, IL
- Average humidity in December: 78%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (70%).
Average rainfall in December
Mason City, IL
- Average rainfall in December: 1.46"
The wettest month (with the highest rainfall) is May (3.98").
The driest month (with the least rainfall) is December (1.46").
Average rainfall days in December
Mason City, IL
- Average rainfall days in December: 8.1 days
The month with the highest number of rainy days is May (18.9 days).
The month with the least rainy days is February (6.2 days).
Average snowfall in December
Mason City, IL
- Average snowfall in December: 1.65"
The month with the highest snowfall is January (3.98").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Mason City, IL
- Average snowfall days in December: 6 days
The month with the highest number of snowfall days is January (10.7 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
Mason City, IL
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in December: 4h and 4min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in December
Mason City, IL
- Average sunshine days in December: 18 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (10.5 days).
Average UV index in December
Mason City, IL
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Mason City, IL
- Average cloud cover in December: 51
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are August and September (Cloud cover 29).
Average visibility in December
Mason City, IL
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Mason City, Illinois, USA
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