December weather forecastShelby, IA
December
Weather in December
December, the first month of the winter in Shelby, is also a wintry month, with temperature in the range of an average high of 33.4°F (0.8°C) and an average low of 21.4°F (-5.9°C).Temperature
A decrease in the average high-temperature is observed during December, shifting from a frosty 47.3°F (8.5°C) in November to a cold 33.4°F (0.8°C). In Shelby, the nighttime temperature averages to a subzero cold 21.4°F (-5.9°C) during December.Humidity
In December, the average relative humidity is 79%.Rainfall
In Shelby, in December, during 5.2 rainfall days, 1.61" (41mm) of precipitation is typically accumulated. Throughout the year, in Shelby, there are 127.7 rainfall days, and 26.57" (675mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. In Shelby, Iowa, in December, snow falls for 8.5 days, with typically accumulated 2.72" (69mm) of snow. Throughout the year, in Shelby, there are 35.8 snowfall days, and 13.82" (351mm) of snow is accumulated.Daylight
With an average of 9h and 12min of daylight, December has the shortest days of the year in Shelby.On the first day of the month, sunrise is at 7:29 am and sunset at 4:52 pm. On the last day of December, sunrise is at 7:48 am and sunset at 5:02 pm CST.
Sunshine
In December, the average sunshine in Shelby is 4.9h.UV index
January, February, October through December, with an average maximum UV index of 2, are months with the lowest UV index in Shelby. A UV Index estimate of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the average person.Note: An average UV index of 2 in December transforms into this advice:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear. 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
Average temperature in December
Shelby, IA
- Average high temperature in December: 33.4°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in December: 21.4°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is January (15.4°F).
Average pressure in December
Shelby, IA
- 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 (29.87"Hg).
Average wind speed in December
Shelby, IA
- Average wind speed in December: 9.9mph
The windiest month (with the highest average wind speed) is April (10.7mph).
The calmest month (with the lowest average wind speed) is July (7mph).
Average humidity in December
Shelby, IA
- Average humidity in December: 79%
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is October (68%).
Average rainfall in December
Shelby, IA
- Average rainfall in December: 1.61"
The wettest month (with the highest rainfall) is June (4.37").
The driest month (with the least rainfall) is January (0.87").
Average rainfall days in December
Shelby, IA
- Average rainfall days in December: 5.2 days
The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is February (3.6 days).
Average snowfall in December
Shelby, IA
- Average snowfall in December: 2.72"
The month with the highest snowfall is February (3.7").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Shelby, IA
- Average snowfall days in December: 8.5 days
The month with the highest number of snowfall days is January (9.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Shelby, IA
- Average daylight in December: 9h and 12min
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 54min
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 36min).
Average sunshine days in December
Shelby, IA
- Average sunshine days in December: 18.7 days
The month with the most sunshine days is November (20.5 days).
The month with the least sunshine days is June (11 days).
Average UV index in December
Shelby, IA
- 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, October, November and December (UV index 2).
Average cloud cover in December
Shelby, IA
- Average cloud cover in December: 47
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility in December
Shelby, IA
- 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).
