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
Grantley's progression into December includes a drop in the average high-temperature, from a fresh 50.9°F (10.5°C) in November to an icy 41.9°F (5.5°C). Grantley's nighttime temperature in December falls to an average of 30.4°F (-0.9°C).Humidity
In Grantley, the average relative humidity in December is 79%.Rainfall
In Grantley, in December, during 8.7 rainfall days, 1.61" (41mm) of precipitation is typically accumulated. In Grantley, during the entire year, the rain falls for 139.8 days and collects up to 22.95" (583mm) of precipitation.Snowfall
Months with snowfall in Grantley are January through May, October through December. In Grantley, Pennsylvania, in December, snow falls for 3 days, with typically accumulated 1.22" (31mm) of snow. In Grantley, during the entire year, snow falls for 18.4 days and aggregates up to 9.13" (232mm) of snow.Daylight
With an average of 9h and 24min of daylight, December has the shortest days of the year.On the first day of December in Grantley, Pennsylvania, sunrise is at 7:10 am and sunset at 4:42 pm. On the last day of the month, sunrise is at 7:28 am and sunset at 4:52 pm EST.
Sunshine
The average sunshine in December is 4.9h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Grantley, Pennsylvania. A UV Index reading of 2, and below, represents a low threat to health from unsafe exposure to UV radiation for the ordinary person.Note: The average daily UV index of 2 in December transforms into the following instructions:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Warning! The reflection from snow can nearly magnify the Sun's UV radiation twofold.
Frequently asked questions
How cold does it get in Grantley in December?
What is the average humidity in December in Grantley?
How much does it rain in Grantley in December?
How much does it snow in Grantley in December?
What is the month with the shortest days in Grantley?
How many hours of daylight does Grantley have in December?
What time are sunrise and sunset in December in Grantley?
How long on average sun shines in December in Grantley?
When is the lowest UV index in Grantley?
What is the UV index reading in December in Grantley?
Average temperature in December
Grantley, PA
- Average high temperature in December: 41.9°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (35.8°F).
- Average low temperature in December: 30.4°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 (23.4°F).
Average pressure in December
Grantley, 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 (29.94"Hg).
Average wind speed in December
Grantley, PA
- Average wind speed in December: 8.2mph
The windiest month (with the highest average wind speed) is March (8.9mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity in December
Grantley, PA
- Average humidity in December: 79%
The month with the highest relative humidity is May (81%).
The months with the lowest relative humidity are March, April and November (76%).
Average rainfall in December
Grantley, PA
- Average rainfall in December: 1.61"
The wettest month (with the highest rainfall) is August (2.8").
The driest month (with the least rainfall) is February (1.26").
Average rainfall days in December
Grantley, PA
- Average rainfall days in December: 8.7 days
The month with the highest number of rainy days is May (15.9 days).
The month with the least rainy days is January (6.3 days).
Average snowfall in December
Grantley, PA
- Average snowfall in December: 1.22"
The month with the highest snowfall is March (3.23").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Grantley, PA
- Average snowfall days in December: 3 days
The month with the highest number of snowfall days is February (5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grantley, PA
- Average daylight in December: 9h and 2min
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 5min
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
Grantley, PA
- Average sunshine days in December: 18.6 days
The month with the most sunshine days is January (20.4 days).
The month with the least sunshine days is May (11.7 days).
Average UV index in December
Grantley, 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, November and December (UV index 2).
Average cloud cover in December
Grantley, PA
- Average cloud cover in December: 47
The months with the most cloud cover are February and March (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in December
Grantley, 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).
Grantley, Pennsylvania, USA
Weather forecast for your location
2. Allow the app to use your location
