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
The start of December signals a decrease in the average high-temperature, transitioning from a cool 52.7°F (11.5°C) in November to a frosty 43.7°F (6.5°C). Cornwell temperatures generally rest at a low of 32.5°F (0.3°C) during the December nights.Humidity
In December, the average relative humidity in Cornwell is 76%.Rainfall
In Cornwell, Pennsylvania, in December, it is raining for 9.8 days, with typically 3.03" (77mm) of accumulated precipitation. In Cornwell, during the entire year, the rain falls for 153.8 days and collects up to 30.94" (786mm) of precipitation.Snowfall
January through May, November and December are months with snowfall. In Cornwell, during December, snow falls for 2.7 days and regularly aggregates up to 1.18" (30mm) of snow. In Cornwell, during the entire year, snow falls for 16.8 days and aggregates up to 8.5" (216mm) of snow.Daylight
December has the shortest days of the year in Cornwell, with an average of 9h and 24min of daylight.On the first day of December in Cornwell, sunrise is at 7:03 am and sunset at 4:34 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 4:44 pm EST.
Sunshine
In Cornwell, the average sunshine in December is 5h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Cornwell. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV rays for average individuals.Note: In December, the maximum UV index of 2 translates into these guidelines:
Infants, children, and people with sensitive skin should always have protection against lengthy periods of sun exposure. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December in Cornwell?
What is the average humidity in December in Cornwell?
How many days does it rain in December in Cornwell?
How many days does it snow in December in Cornwell?
What is the month with the shortest days in Cornwell?
What is the average length of the day in December in Cornwell?
What time are sunrise and sunset in December in Cornwell?
How long on average sun shines in December in Cornwell?
What is the month with the lowest UV index in Cornwell?
What is the UV index reading in December in Cornwell?
Average temperature in December
Cornwell, PA
- Average high temperature in December: 43.7°F
The warmest month (with the highest average high temperature) is July (86.4°F).
The month with the lowest average high temperature is January (37.4°F).
- Average low temperature in December: 32.5°F
The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure in December
Cornwell, PA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Cornwell, PA
- Average wind speed in December: 7.7mph
The windiest months (with the highest average wind speed) are March and April (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in December
Cornwell, PA
- Average humidity in December: 76%
The months with the highest relative humidity are February and October (77%).
The months with the lowest relative humidity are April, July and August (71%).
Average rainfall in December
Cornwell, PA
- Average rainfall in December: 3.03"
The wettest month (with the highest rainfall) is July (3.39").
The driest month (with the least rainfall) is January (1.89").
Average rainfall days in December
Cornwell, PA
- Average rainfall days in December: 9.8 days
The month with the highest number of rainy days is July (18.5 days).
The month with the least rainy days is November (7.5 days).
Average snowfall in December
Cornwell, PA
- Average snowfall in December: 1.18"
The month with the highest snowfall is March (2.76").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Cornwell, PA
- Average snowfall days in December: 2.7 days
The month with the highest number of snowfall days is January (5.2 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Cornwell, PA
- Average daylight in December: 9h and 2min
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: 5h and 0min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in December
Cornwell, PA
- Average sunshine days in December: 19 days
The month with the most sunshine days is November (21.2 days).
The month with the least sunshine days is July (10.4 days).
Average UV index in December
Cornwell, PA
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (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
Cornwell, PA
- Average cloud cover in December: 47
The month with the most cloud cover is February (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in December
Cornwell, PA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).
Cornwell, Pennsylvania, USA
Weather forecast for your location
2. Allow the app to use your location