December weather forecastMonroeville, PA
December
Weather in December
The first month of the winter, December, is also a wintry month in Monroeville, Pennsylvania, with temperature in the range of an average high of 39.4°F (4.1°C) and an average low of 28.2°F (-2.1°C).Temperature
The arrival of December corresponds with a reduction in the average high-temperature, down from November's frosty 49.1°F (9.5°C) to a wintry 39.4°F (4.1°C). In Monroeville, the December nights cool down to an average low of 28.2°F (-2.1°C).Humidity
In December, the average relative humidity in Monroeville is 84%.Rainfall
In December, the rain falls for 9.3 days. Throughout December, 1.54" (39mm) of precipitation is accumulated. Throughout the year, there are 151 rainfall days, and 20.39" (518mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. In December, it is snowing for 6.2 days. Throughout December, 1.81" (46mm) of snow is accumulated. In Monroeville, during the entire year, snow falls for 35.4 days and aggregates up to 10.35" (263mm) of snow.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:23 am and sunset at 4:53 pm. On the last day of the month, sunrise is at 7:42 am and sunset at 5:02 pm EST.
Sunshine
In Monroeville, Pennsylvania, the average sunshine in December is 3.3h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: The daily high UV index of 1 in December translates into this advice:
While most individuals can withstand prolonged sun exposure, it is imperative that babies, children, and those with sensitive skin always be shielded. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Attention! Nearly twice the Sun's UV radiation can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Monroeville, PA
- Average high temperature in December: 39.4°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (33.1°F).
- Average low temperature in December: 28.2°F
The month with the highest average low temperature is July (61.3°F).
The coldest month (with the lowest average low temperature) is January (20.7°F).
Average pressure in December
Monroeville, PA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in December
Monroeville, PA
- Average wind speed in December: 7.5mph
The windiest month (with the highest average wind speed) is January (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.7mph).
Average humidity in December
Monroeville, PA
- Average humidity in December: 84%
The month with the highest relative humidity is February (85%).
The months with the lowest relative humidity are April, July and August (76%).
Average rainfall in December
Monroeville, PA
- Average rainfall in December: 1.54"
The wettest month (with the highest rainfall) is May (2.56").
The driest month (with the least rainfall) is November (1.06").
Average rainfall days in December
Monroeville, PA
- Average rainfall days in December: 9.3 days
The month with the highest number of rainy days is May (18.2 days).
The month with the least rainy days is January (7.7 days).
Average snowfall in December
Monroeville, PA
- Average snowfall in December: 1.81"
The month with the highest snowfall is February (2.52").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Monroeville, PA
- Average snowfall days in December: 6.2 days
The month with the highest number of snowfall days is January (9.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Monroeville, PA
- Average daylight in December: 9h and 18min
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 18min).
- Average sunshine in December: 3h and 18min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 2h and 54min).
Average sunshine days in December
Monroeville, PA
- Average sunshine days in December: 17.1 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is May (10.1 days).
Average UV index in December
Monroeville, PA
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Monroeville, PA
- Average cloud cover in December: 65
The month with the most cloud cover is January (Cloud cover 69).
The month with the least cloud cover is August (Cloud cover 33).
Average visibility in December
Monroeville, PA
- Average visibility in December: 5mi
The months with the highest visibility are April, June, August and November (6mi).
The months with the lowest visibility are January, February, March, May, July, September, October and December (5mi).
