Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
As November shifts into December, a slight alteration in temperatures is observed, with average highs reducing from a chilly 47.3°F (8.5°C) to a wintry 37.6°F (3.1°C). In Grassmere Park, December nights witness a steady temperature drop to a freezing cold 27°F (-2.8°C).Humidity
In Grassmere Park, the average relative humidity in December is 82%.Rainfall
In Grassmere Park, in December, during 12.4 rainfall days, 2.52" (64mm) of precipitation is typically accumulated. Throughout the year, there are 166.3 rainfall days, and 31.06" (789mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Grassmere Park, in December, during 9.4 snowfall days, 3.94" (100mm) of snow is typically accumulated. Throughout the year, there are 47.6 snowfall days, and 22.91" (582mm) of snow is accumulated.Daylight
December has the shortest days of the year in Grassmere Park, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:12 am and sunset at 4:37 pm. On the last day of December, sunrise is at 7:31 am and sunset at 4:46 pm EST.
Sunshine
The average sunshine in December in Grassmere Park is 4.1h.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 ordinary individuals.Note: In December, the maximum UV index of 1 suggests this advice:
Most individuals face no major issues with lengthy exposure to the sun, but children, infants, and individuals with fair skin always require protection. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes. Take heed! Reflection from the snow can almost amplify the Sun's UV radiation by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold does it get in December?
What is the average humidity in December?
How many days does it rain in December in Grassmere Park?
How many days does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Grassmere Park have in December?
When are sunrise and sunset in December?
How long on average sun shines in December?
When is the lowest UV index?
How high is the UV index in December in Grassmere Park?
Average temperature in December
Grassmere Park, PA
- Average high temperature in December: 37.6°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (31.8°F).
- Average low temperature in December: 27°F
The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is January (19°F).
Average pressure in December
Grassmere Park, PA
- Average pressure in December: 30.09"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
Grassmere Park, PA
- Average wind speed in December: 7.5mph
The windiest months (with the highest average wind speed) are March and April (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Grassmere Park, PA
- Average humidity in December: 82%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is April (77%).
Average rainfall in December
Grassmere Park, PA
- Average rainfall in December: 2.52"
The wettest months (with the highest rainfall) are April and May (2.99").
The driest month (with the least rainfall) is September (2.05").
Average rainfall days in December
Grassmere Park, PA
- Average rainfall days in December: 12.4 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is January (9.3 days).
Average snowfall in December
Grassmere Park, PA
- Average snowfall in December: 3.94"
The month with the highest snowfall is January (5.94").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Grassmere Park, PA
- Average snowfall days in December: 9.4 days
The month with the highest number of snowfall days is January (12.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grassmere Park, PA
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 4h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 3h and 48min).
Average sunshine days in December
Grassmere Park, PA
- Average sunshine days in December: 12.5 days
The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is February (9.8 days).
Average UV index in December
Grassmere Park, PA
- Average UV index in December: 1
The months with the highest UV index are May, June, July and August (UV index 5).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Grassmere Park, PA
- Average cloud cover in December: 58
The months with the most cloud cover are February and December (Cloud cover 58).
The month with the least cloud cover is July (Cloud cover 35).
Average visibility in December
Grassmere Park, 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).
Grassmere Park, Pennsylvania, USA
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