December weather forecastUpper Glasgow, PA
December
Weather in December
The first month of the winter, December, is also an icy month in Upper Glasgow, Pennsylvania, with an average temperature varying between 30.2°F (-1°C) and 41.5°F (5.3°C).Temperature
In Upper Glasgow, entering December brings a temperature decrement, reducing from November's fresh 50.7°F (10.4°C) to an icy 41.5°F (5.3°C). Throughout December, a steady low-temperature average of 30.2°F (-1°C) is noted.Humidity
In December, the average relative humidity is 79%.Rainfall
In Upper Glasgow, in December, during 9.5 rainfall days, 2.32" (59mm) of precipitation is typically accumulated. Throughout the year, there are 146.5 rainfall days, and 27.87" (708mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In Upper Glasgow, in December, snow falls for 2.7 days, with typically accumulated 1.89" (48mm) of snow. Throughout the year, there are 19.1 snowfall days, and 11.54" (293mm) 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 7:06 am and sunset at 4:37 pm. On the last day of the month, sunrise is at 7:25 am and sunset at 4:46 pm EST.
Sunshine
The average sunshine in December is 4.9h.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 reading of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for average individuals.Note: The daily maximum UV index of 2 in December interprets into the following advice:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. Around midday, solar radiation is most harmful; hence, exposure should be limited. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection. Be on the lookout! Nearly twofold UV radiation from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Upper Glasgow, PA
- Average high temperature in December: 41.5°F
The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (35.4°F).
- Average low temperature in December: 30.2°F
The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (23.2°F).
Average pressure in December
Upper Glasgow, 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
Upper Glasgow, PA
- Average wind speed in December: 7.6mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Upper Glasgow, PA
- Average humidity in December: 79%
The months with the highest relative humidity are February and October (80%).
The months with the lowest relative humidity are April and July (75%).
Average rainfall in December
Upper Glasgow, PA
- Average rainfall in December: 2.32"
The wettest month (with the highest rainfall) is August (3.15").
The driest month (with the least rainfall) is September (1.81").
Average rainfall days in December
Upper Glasgow, PA
- Average rainfall days in December: 9.5 days
The months with the highest number of rainy days are May and July (17 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in December
Upper Glasgow, PA
- Average snowfall in December: 1.89"
The month with the highest snowfall is March (3.7").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Upper Glasgow, PA
- Average snowfall days in December: 2.7 days
The month with the highest number of snowfall days is January (5.8 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
Upper Glasgow, 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 54min
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 42min).
Average sunshine days in December
Upper Glasgow, PA
- Average sunshine days in December: 19.4 days
The month with the most sunshine days is November (21 days).
The month with the least sunshine days is May (12.3 days).
Average UV index in December
Upper Glasgow, 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
Upper Glasgow, 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
Upper Glasgow, 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).





