December weather forecastYerkes, PA
December
Weather in December
December, the first month of the winter in Yerkes, is also a wintry month, with an average temperature fluctuating between 30.9°F (-0.6°C) and 42.3°F (5.7°C).Temperature
December signals a slight drop in average high-temperature, sliding from November's fresh 51.1°F (10.6°C) to an icy 42.3°F (5.7°C). Throughout the nights in December, an average low-temperature of 30.9°F (-0.6°C) is noted.Humidity
The average relative humidity in December is 79%.Rainfall
In Yerkes, during December, the rain falls for 7.9 days and regularly aggregates up to 0.98" (25mm) of precipitation. Throughout the year, there are 132.3 rainfall days, and 13.98" (355mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through March, November and December. In December, it is snowing for 2.5 days. Throughout December, 0.51" (13mm) of snow is accumulated. Throughout the year, there are 15.1 snowfall days, and 2.2" (56mm) 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 December, sunrise is at 7:05 am and sunset at 4:36 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 4:46 pm EST.
Sunshine
In Yerkes, the average sunshine in December is 4.8h.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 reading of 2, and below, represents a minimal health hazard from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A daily maximum UV index of 2 in December translates into the following instructions:
Apart from children, who require continuous protection, most can endure sun exposure for up to an hour without experiencing burns. The Sun is most powerful around mid-day, so it's a good practice to reduce direct exposure. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear. Warning! The reflection from snow can nearly magnify 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
Yerkes, PA
- Average high temperature in December: 42.3°F
The warmest month (with the highest average high temperature) is July (85.1°F).
The month with the lowest average high temperature is January (36°F).
- Average low temperature in December: 30.9°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (23.9°F).
Average pressure in December
Yerkes, PA
- Average pressure in December: 30.1"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
Yerkes, PA
- Average wind speed in December: 7.7mph
The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in December
Yerkes, PA
- Average humidity in December: 79%
The month with the highest relative humidity is February (80%).
The months with the lowest relative humidity are April and July (74%).
Average rainfall in December
Yerkes, PA
- Average rainfall in December: 0.98"
The wettest month (with the highest rainfall) is August (1.77").
The driest month (with the least rainfall) is February (0.75").
Average rainfall days in December
Yerkes, PA
- Average rainfall days in December: 7.9 days
The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is January (6.9 days).
Average snowfall in December
Yerkes, PA
- Average snowfall in December: 0.51"
The months with the highest snowfall are January and February (0.59").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Yerkes, PA
- Average snowfall days in December: 2.5 days
The month with the highest number of snowfall days is February (4.9 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Yerkes, 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 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Yerkes, PA
- Average sunshine days in December: 20.4 days
The month with the most sunshine days is January (20.7 days).
The month with the least sunshine days is June (12.8 days).
Average UV index in December
Yerkes, 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
Yerkes, 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
Yerkes, 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).





