December weather forecastDarby, PA
December
Weather in December
December, the first month of the winter in Darby, is still a chilly month, with an average temperature ranging between max 44.1°F (6.7°C) and min 32.7°F (0.4°C).Temperature
December's onset corresponds with a subtle shift in the average high-temperature, slightly moving from a cool 52.7°F (11.5°C) in November to a frosty 44.1°F (6.7°C). Darby's average low-temperature is measured at an icy 32.7°F (0.4°C) during December.Humidity
The months with the highest humidity are February, October and December, with an average relative humidity of 77%.Rainfall
In December, the rain falls for 9.6 days. Throughout December, 2.4" (61mm) of precipitation is accumulated. In Darby, during the entire year, the rain falls for 142 days and collects up to 24.41" (620mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Darby, in December, during 1.5 snowfall days, 0.75" (19mm) of snow is typically accumulated. Throughout the year, there are 11.3 snowfall days, and 6.18" (157mm) of snow is accumulated.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 7:04 am and sunset at 4:36 pm. On the last day of December, sunrise is at 7:22 am and sunset at 4:46 pm EST.
Sunshine
In Darby, the average sunshine in December is 5.1h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from unprotected exposure to Sun's UV rays for average individuals.Note: A maximum high daily UV index of 2 during December translates into the following directions:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Darby, PA
- Average high temperature in December: 44.1°F
The warmest month (with the highest average high temperature) is July (86°F).
The month with the lowest average high temperature is January (37.4°F).
- Average low temperature in December: 32.7°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in December
Darby, 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 (29.94"Hg).
Average wind speed in December
Darby, PA
- Average wind speed in December: 7.8mph
The windiest months (with the highest average wind speed) are February, March and April (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in December
Darby, PA
- Average humidity in December: 77%
The months with the highest relative humidity are February, October and December (77%).
The month with the lowest relative humidity is April (71%).
Average rainfall in December
Darby, PA
- Average rainfall in December: 2.4"
The wettest month (with the highest rainfall) is August (2.95").
The driest month (with the least rainfall) is January (1.46").
Average rainfall days in December
Darby, PA
- Average rainfall days in December: 9.6 days
The month with the highest number of rainy days is July (16.9 days).
The month with the least rainy days is January (6.6 days).
Average snowfall in December
Darby, PA
- Average snowfall in December: 0.75"
The month with the highest snowfall is March (2.05").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Darby, PA
- Average snowfall days in December: 1.5 days
The month with the highest number of snowfall days is January (3.3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Darby, 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: 5h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 54min).
Average sunshine days in December
Darby, PA
- Average sunshine days in December: 19.7 days
The month with the most sunshine days is January (20.8 days).
The month with the least sunshine days is July (12.1 days).
Average UV index in December
Darby, 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, November and December (UV index 2).
Average cloud cover in December
Darby, PA
- Average cloud cover in December: 46
The month with the most cloud cover is February (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 30).
Average visibility in December
Darby, PA
- 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).





