December weather forecastHarley, IN
December
Weather in December
December, the first month of the winter in Harley, is also a wintry month, with an average temperature ranging between max 37°F (2.8°C) and min 27.1°F (-2.7°C).Temperature
Harley's average high-temperature decreases in December, falling from a frosty 48.2°F (9°C) in November to an icy 37°F (2.8°C). Harley records a consistent low-temperature of 27.1°F (-2.7°C) during December nights.Humidity
In December, the average relative humidity is 82%.Rainfall
The month with the least rainfall is December, when the rain falls for 8.6 days and typically collects 1.18" (30mm) of precipitation.Snowfall
Months with snowfall are January through April, October through December. In Harley, in December, during 7.2 snowfall days, 1.46" (37mm) of snow is typically accumulated. In Harley, during the entire year, snow falls for 37.1 days and aggregates up to 8.15" (207mm) of snow.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:51 am and sunset at 5:20 pm. On the last day of the month, sunrise is at 8:09 am and sunset at 5:29 pm EST.
Sunshine
In December, the average sunshine is 4.2h.UV index
The month with the lowest UV index is December, with an average maximum UV index of 1. A UV Index estimate of 2, and below, represents a minimal health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The daily high UV index of 1 in December translates into this advice:
Most individuals can handle sun exposure for up to an hour without burning, but children must always be shielded from sun exposure. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Harley, IN
- Average high temperature in December: 37°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (31.3°F).
- Average low temperature in December: 27.1°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (19.4°F).
Average pressure in December
Harley, IN
- Average pressure in December: 30.11"Hg
The months with the highest atmospheric pressure are January and November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Harley, IN
- Average wind speed in December: 9.5mph
The windiest month (with the highest average wind speed) is January (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (6.2mph).
Average humidity in December
Harley, IN
- Average humidity in December: 82%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is October (72%).
Average rainfall in December
Harley, IN
- Average rainfall in December: 1.18"
The wettest month (with the highest rainfall) is April (2.64").
The driest month (with the least rainfall) is December (1.18").
Average rainfall days in December
Harley, IN
- Average rainfall days in December: 8.6 days
The month with the highest number of rainy days is May (18.1 days).
The month with the least rainy days is January (6 days).
Average snowfall in December
Harley, IN
- Average snowfall in December: 1.46"
The month with the highest snowfall is February (2.44").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Harley, IN
- Average snowfall days in December: 7.2 days
The month with the highest number of snowfall days is January (11.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Harley, IN
- Average daylight in December: 9h and 18min
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 18min).
- Average sunshine in December: 4h and 12min
The months with the most sunshine are June and July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in December
Harley, IN
- Average sunshine days in December: 16.8 days
The month with the most sunshine days is November (18.6 days).
The month with the least sunshine days is May (11.2 days).
Average UV index in December
Harley, IN
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Harley, IN
- Average cloud cover in December: 57
The month with the most cloud cover is January (Cloud cover 61).
The months with the least cloud cover are June and August (Cloud cover 33).
Average visibility in December
Harley, IN
- 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).
