December weather forecastCornwall, CT
December
Weather in December
December, the first month of the winter in Cornwall, is still a cold month, with an average temperature fluctuating between 36.7°F (2.6°C) and 25.7°F (-3.5°C).Temperature
Cornwall in December experiences a subtle temperature decline, with average high-temperatures reducing from a frosty 46.6°F (8.1°C) in November to a wintry 36.7°F (2.6°C). The low-temperature average for Cornwall during December stands at a freezing cold 25.7°F (-3.5°C).Humidity
The average relative humidity in December is 81%.Rainfall
In Cornwall, in December, it is raining for 10.9 days, with typically 3.35" (85mm) of accumulated precipitation. Throughout the year, there are 160.5 rainfall days, and 33.86" (860mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. In Cornwall, in December, during 7.1 snowfall days, 3.7" (94mm) of snow is typically accumulated. In Cornwall, during the entire year, snow falls for 40.2 days and aggregates up to 20.39" (518mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:01 am and sunset at 4:23 pm. On the last day of the month, sunrise is at 7:20 am and sunset at 4:32 pm EST.
Sunshine
In Cornwall, Connecticut, the average sunshine in December is 4.5h.UV index
January through March, November and 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 threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In December, the UV index of 2 transforms into the following advice:
Children must always have sun protection, unlike most people, who can tolerate up to an hour in the sun without any burns. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Cornwall, CT
- Average high temperature in December: 36.7°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (30.9°F).
- Average low temperature in December: 25.7°F
The month with the highest average low temperature is July (61.3°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in December
Cornwall, CT
- Average pressure in December: 30.06"Hg
The month with the highest atmospheric pressure is November (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Cornwall, CT
- Average wind speed in December: 7.5mph
The windiest months (with the highest average wind speed) are January and March (8mph).
The calmest months (with the lowest average wind speed) are July and August (5mph).
Average humidity in December
Cornwall, CT
- Average humidity in December: 81%
The month with the highest relative humidity is February (82%).
The month with the lowest relative humidity is April (74%).
Average rainfall in December
Cornwall, CT
- Average rainfall in December: 3.35"
The wettest month (with the highest rainfall) is July (3.54").
The driest month (with the least rainfall) is January (2.17").
Average rainfall days in December
Cornwall, CT
- Average rainfall days in December: 10.9 days
The month with the highest number of rainy days is July (17.9 days).
The month with the least rainy days is January (7.7 days).
Average snowfall in December
Cornwall, CT
- Average snowfall in December: 3.7"
The month with the highest snowfall is February (5.16").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Cornwall, CT
- Average snowfall days in December: 7.1 days
The month with the highest number of snowfall days is February (10.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Cornwall, CT
- Average daylight in December: 9h and 12min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 4h and 30min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is February (Average sunshine: 4h and 12min).
Average sunshine days in December
Cornwall, CT
- Average sunshine days in December: 14.8 days
The month with the most sunshine days is January (16.8 days).
The month with the least sunshine days is June (10.8 days).
Average UV index in December
Cornwall, CT
- Average UV index in December: 2
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in December
Cornwall, CT
- Average cloud cover in December: 52
The month with the most cloud cover is February (Cloud cover 53).
The months with the least cloud cover are July and August (Cloud cover 37).
Average visibility in December
Cornwall, CT
- Average visibility in December: 5mi
The months with the highest visibility are April and November (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October and December (5mi).
