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
A shift in the average high-temperature occurs in December, reducing from a frosty 46.9°F (8.3°C) in November to a wintry 34.7°F (1.5°C). During the month of December, Harper anticipates a mean low-temperature of 23.4°F (-4.8°C).Humidity
The average relative humidity in December is 80%.Rainfall
In Harper, in December, it is raining for 6.8 days, with typically 1.18" (30mm) of accumulated precipitation. In Harper, during the entire year, the rain falls for 137.9 days and collects up to 27.76" (705mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Harper, in December, during 6.5 snowfall days, 1.34" (34mm) of snow is typically accumulated. In Harper, during the entire year, snow falls for 32.8 days and aggregates up to 12.56" (319mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 7:15 am and sunset at 4:39 pm. On the last day of December, sunrise is at 7:34 am and sunset at 4:48 pm CST.
Sunshine
The average sunshine in December is 4.6h.UV index
January, February, October through December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for average individuals.Note: The average daily UV index of 2 in December transforms into the following instructions:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
How much does it rain in Harper in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When is the sunrise / sunset in December?
How many hours of sunshine does Harper have in December?
What is the month with the lowest UV index?
What is the UV index intensity in December in Harper?
Average temperature in December
Harper, IA
- Average high temperature in December: 34.7°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (28.6°F).
- Average low temperature in December: 23.4°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 (15.6°F).
Average pressure in December
Harper, IA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in December
Harper, IA
- Average wind speed in December: 10.1mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest month (with the lowest average wind speed) is August (6.9mph).
Average humidity in December
Harper, IA
- Average humidity in December: 80%
The month with the highest relative humidity is July (83%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Harper, IA
- Average rainfall in December: 1.18"
The wettest month (with the highest rainfall) is May (4.17").
The driest month (with the least rainfall) is February (0.98").
Average rainfall days in December
Harper, IA
- Average rainfall days in December: 6.8 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (4.9 days).
Average snowfall in December
Harper, IA
- Average snowfall in December: 1.34"
The month with the highest snowfall is January (4.06").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Harper, IA
- Average snowfall days in December: 6.5 days
The month with the highest number of snowfall days is January (9.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Harper, 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 4min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in December
Harper, IA
- Average sunshine days in December: 19.1 days
The month with the most sunshine days is December (19.1 days).
The month with the least sunshine days is June (10.3 days).
Average UV index in December
Harper, 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, February, October, November and December (UV index 2).
Average cloud cover in December
Harper, IA
- Average cloud cover in December: 52
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
Harper, IA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).
Harper, Iowa, USA
Weather forecast for your location
2. Allow the app to use your location