December weather forecastOrrstown, PA
December
Weather in December
The first month of the winter, December, is also an icy month in Orrstown, Pennsylvania, with an average temperature varying between 40.8°F (4.9°C) and 28.9°F (-1.7°C).Temperature
Start of December brings a shift in the average high-temperature, falling from November's fresh 50°F (10°C) to an icy 40.8°F (4.9°C). Orrstown experiences an average low-temperature of 28.9°F (-1.7°C) in the month of December.Humidity
In December, the average relative humidity is 79%.Rainfall
In Orrstown, in December, it is raining for 10.8 days, with typically 2.05" (52mm) of accumulated precipitation. In Orrstown, Pennsylvania, during the entire year, the rain falls for 156 days and collects up to 27.2" (691mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Orrstown, during December, snow falls for 4.2 days and regularly aggregates up to 1.73" (44mm) of snow. In Orrstown, during the entire year, snow falls for 28.8 days and aggregates up to 15.39" (391mm) of snow.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of December, sunrise is at 7:13 am and sunset at 4:45 pm. On the last day of the month, sunrise is at 7:32 am and sunset at 4:55 pm EST.
Sunshine
In December, the average sunshine in Orrstown is 4.6h.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 estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV radiation for the average person.Note: During December, 2 as the daily maximum UV index converts into the following advice:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. Around midday, solar radiation is most harmful; hence, exposure should be limited. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days. Consider this! The reflection from snow can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Orrstown, PA
- Average high temperature in December: 40.8°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (35.1°F).
- Average low temperature in December: 28.9°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (22.1°F).
Average pressure in December
Orrstown, PA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in December
Orrstown, PA
- Average wind speed in December: 7.2mph
The windiest month (with the highest average wind speed) is January (7.8mph).
The calmest month (with the lowest average wind speed) is August (4.5mph).
Average humidity in December
Orrstown, PA
- Average humidity in December: 79%
The months with the highest relative humidity are February and October (80%).
The month with the lowest relative humidity is July (75%).
Average rainfall in December
Orrstown, PA
- Average rainfall in December: 2.05"
The wettest month (with the highest rainfall) is May (2.95").
The driest month (with the least rainfall) is January (1.85").
Average rainfall days in December
Orrstown, PA
- Average rainfall days in December: 10.8 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in December
Orrstown, PA
- Average snowfall in December: 1.73"
The month with the highest snowfall is January (4.92").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Orrstown, PA
- Average snowfall days in December: 4.2 days
The month with the highest number of snowfall days is January (8.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Orrstown, 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 36min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).
Average sunshine days in December
Orrstown, PA
- Average sunshine days in December: 16.6 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (11.6 days).
Average UV index in December
Orrstown, PA
- Average UV index in December: 2
The months with the highest UV index are June and July (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
Orrstown, PA
- Average cloud cover in December: 52
The months with the most cloud cover are January, February and December (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in December
Orrstown, PA
- Average visibility in December: 6mi
The months with the highest visibility are April, June, July, November and December (6mi).
The months with the lowest visibility are January, February, March, May, August, September and October (5mi).
