December weather forecastCastleton, IN
December
Weather in December
December, the first month of the winter in Castleton, is also an icy month, with an average temperature fluctuating between 27.7°F (-2.4°C) and 38.1°F (3.4°C).Temperature
Welcoming December, Castleton observes a shift in the average high-temperature, falling from November's chilly 48.9°F (9.4°C) to a cold 38.1°F (3.4°C). An average nighttime temperature of 27.7°F (-2.4°C) is noted during the month of December.Humidity
January and December, with an average relative humidity of 83%, are the most humid months.Rainfall
In Castleton, in December, during 8 rainfall days, 1.5" (38mm) of precipitation is typically accumulated. Throughout the year, there are 141 rainfall days, and 20.98" (533mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall. In December, it is snowing for 6.4 days. Throughout December, 1.93" (49mm) of snow is accumulated. In Castleton, Indiana, during the entire year, snow falls for 29.1 days and aggregates up to 7.99" (203mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 24min of daylight.On the first day of the month, sunrise is at 7:47 am and sunset at 5:19 pm. On the last day of December, sunrise is at 8:05 am and sunset at 5:29 pm EST.
Sunshine
In December, the average sunshine is 4.1h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: In December, a daily UV index of 1 turns into the following recommendations:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Stay alert! Snow's reflective properties can almost double the UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Castleton, IN
- Average high temperature in December: 38.1°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in December: 27.7°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (20.7°F).
Average pressure in December
Castleton, IN
- Average pressure in December: 30.12"Hg
The months with the highest atmospheric pressure are January and November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Castleton, IN
- Average wind speed in December: 9.3mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in December
Castleton, IN
- Average humidity in December: 83%
The months with the highest relative humidity are January and December (83%).
The month with the lowest relative humidity is October (74%).
Average rainfall in December
Castleton, IN
- Average rainfall in December: 1.5"
The wettest month (with the highest rainfall) is May (2.64").
The driest month (with the least rainfall) is February (1.18").
Average rainfall days in December
Castleton, IN
- Average rainfall days in December: 8 days
The month with the highest number of rainy days is May (17.4 days).
The month with the least rainy days is January (6 days).
Average snowfall in December
Castleton, IN
- Average snowfall in December: 1.93"
The month with the highest snowfall is February (2.01").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Castleton, IN
- Average snowfall days in December: 6.4 days
The month with the highest number of snowfall days is January (8.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Castleton, IN
- Average daylight in December: 9h and 24min
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 6min
The months with the most sunshine are June and July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in December
Castleton, IN
- Average sunshine days in December: 17.5 days
The months with the most sunshine days are October and November (18.7 days).
The month with the least sunshine days is May (11.3 days).
Average UV index in December
Castleton, IN
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Castleton, IN
- Average cloud cover in December: 58
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 31).
Average visibility in December
Castleton, IN
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





