December weather forecastPalo Alto, PA
December
Weather in December
The first month of the winter, December, is also an icy month in Palo Alto, Pennsylvania, with an average temperature ranging between min 27.7°F (-2.4°C) and max 38.8°F (3.8°C).Temperature
The arrival of December signals a shift in temperature, down from a frosty 48°F (8.9°C) in November to an icy 38.8°F (3.8°C). An average low-temperature of 27.7°F (-2.4°C) is common during the nights of December.Humidity
In December, the average relative humidity is 81%.Rainfall
In December, in Palo Alto, the rain falls for 13.5 days. Throughout December, 2.87" (73mm) of precipitation is accumulated. Throughout the year, there are 172.9 rainfall days, and 34.21" (869mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. In December, it is snowing for 6.9 days. Throughout December, 2.8" (71mm) of snow is accumulated. Throughout the year, there are 39.7 snowfall days, and 20.47" (520mm) of snow is accumulated.Daylight
The month with the shortest days in Palo Alto is December, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:09 am and sunset at 4:38 pm. On the last day of the month, sunrise is at 7:28 am and sunset at 4:47 pm EST.
Sunshine
The months with the least sunshine are January, February and December, with an average of 4.4h of sunshine.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 value of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 2 during December translates into the following directions:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense. Caution! The reflection of snow can nearly 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
Palo Alto, PA
- Average high temperature in December: 38.8°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in December: 27.7°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 (20.5°F).
Average pressure in December
Palo Alto, PA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Palo Alto, PA
- Average wind speed in December: 7.7mph
The windiest month (with the highest average wind speed) is March (8.4mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Palo Alto, PA
- Average humidity in December: 81%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is April (77%).
Average rainfall in December
Palo Alto, PA
- Average rainfall in December: 2.87"
The wettest month (with the highest rainfall) is May (3.39").
The driest month (with the least rainfall) is September (2.09").
Average rainfall days in December
Palo Alto, PA
- Average rainfall days in December: 13.5 days
The month with the highest number of rainy days is May (18.7 days).
The months with the least rainy days are January and November (10.8 days).
Average snowfall in December
Palo Alto, PA
- Average snowfall in December: 2.8"
The month with the highest snowfall is January (5.47").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Palo Alto, PA
- Average snowfall days in December: 6.9 days
The month with the highest number of snowfall days is January (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Palo Alto, 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: 4h and 24min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The months with the least sunshine are January, February and December (Average sunshine: 4h and 24min).
Average sunshine days in December
Palo Alto, PA
- Average sunshine days in December: 14.2 days
The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is May (9.6 days).
Average UV index in December
Palo Alto, PA
- Average UV index in December: 2
The month with the highest UV index is 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
Palo Alto, PA
- Average cloud cover in December: 53
The months with the most cloud cover are February and December (Cloud cover 53).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in December
Palo Alto, PA
- Average visibility in December: 5mi
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).
