December weather forecastDowningtown, PA
December
Weather in December
Closing off the year, Downingtown experiences a full return of winter in December. With temperatures dropping further to a biting low of 30.6°F (-0.8°C), it is indeed the coldest month. The city sets into a festive mood, prepping for the Christmas season amidst a potential white landscape. The previous month’s waning fall colors give way to occasional snowfalls, welcoming the New Year with a fresh coat of snow.Temperature
In Downingtown, the average high-temperature in December drops from a fresh 50.9°F (10.5°C) in November to a wintry 41.9°F (5.5°C). In Downingtown, an average nighttime temperature of 30.6°F (-0.8°C) is expected during December.Humidity
In Downingtown, the average relative humidity in December is 79%.Rainfall
In December, the rain falls for 8.6 days. Throughout December, 2.05" (52mm) of precipitation is accumulated. Throughout the year, there are 145.6 rainfall days, and 26.81" (681mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Downingtown, in December, snow falls for 2 days, with typically accumulated 1.54" (39mm) of snow. In Downingtown, during the entire year, snow falls for 17.2 days and aggregates up to 10.47" (266mm) 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 December, sunrise is at 7:06 am and sunset at 4:38 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 4:47 pm EST.
Sunshine
In Downingtown, the average sunshine in December is 4.8h.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV radiation for the average person.Note: The UV index of 2 in December translates into these instructions:
Unlike children, who always need sun protection, most individuals can remain in the sun for up to an hour without getting burnt. To guard against the harmful effects of the Sun, minimize exposure during midday. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days. 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
Average temperature in December
Downingtown, PA
- Average high temperature in December: 41.9°F
The warmest month (with the highest average high temperature) is July (84°F).
The month with the lowest average high temperature is January (35.4°F).
- Average low temperature in December: 30.6°F
The month with the highest average low temperature is July (66.2°F).
The coldest month (with the lowest average low temperature) is January (23.7°F).
Average pressure in December
Downingtown, PA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Downingtown, PA
- Average wind speed in December: 8mph
The windiest months (with the highest average wind speed) are January and March (8.5mph).
The calmest months (with the lowest average wind speed) are July and August (5.2mph).
Average humidity in December
Downingtown, PA
- Average humidity in December: 79%
The months with the highest relative humidity are February, May and October (80%).
The month with the lowest relative humidity is April (75%).
Average rainfall in December
Downingtown, PA
- Average rainfall in December: 2.05"
The wettest month (with the highest rainfall) is August (3.31").
The driest month (with the least rainfall) is February (1.61").
Average rainfall days in December
Downingtown, PA
- Average rainfall days in December: 8.6 days
The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is January (6.7 days).
Average snowfall in December
Downingtown, PA
- Average snowfall in December: 1.54"
The month with the highest snowfall is March (3.46").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Downingtown, PA
- Average snowfall days in December: 2 days
The month with the highest number of snowfall days is February (4.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Downingtown, PA
- 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 48min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Downingtown, PA
- Average sunshine days in December: 20.5 days
The month with the most sunshine days is December (20.5 days).
The month with the least sunshine days is May (12.3 days).
Average UV index in December
Downingtown, 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
Downingtown, PA
- Average cloud cover in December: 48
The month with the most cloud cover is February (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in December
Downingtown, 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).
