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
Setting in of December comes with a decrease in the average high-temperature, moving from a fresh 50.5°F (10.3°C) in November to an icy 41°F (5°C). In December, the temperature drops to an average of 29.7°F (-1.3°C) at night.Humidity
In Grantham, the average relative humidity in December is 79%.Rainfall
In Grantham, during December, the rain falls for 9.5 days and regularly aggregates up to 1.26" (32mm) of precipitation. Throughout the year, there are 137.7 rainfall days, and 18.43" (468mm) of precipitation is accumulated.Snowfall
January through April, October through December are months with snowfall in Grantham. In Grantham, in December, during 4.4 snowfall days, 1.14" (29mm) of snow is typically accumulated. In Grantham, Pennsylvania, during the entire year, snow falls for 23.7 days and aggregates up to 8.62" (219mm) of snow.Daylight
The month with the shortest days in Grantham is December, with an average of 9h and 24min of daylight.On the first day of the month, sunrise is at 7:11 am and sunset at 4:42 pm. On the last day of December, in Grantham, sunrise is at 7:30 am and sunset at 4:52 pm EST.
Sunshine
In December, the average sunshine is 4.8h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Grantham. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: In December, a daily UV index of 2 turns into the following recommendations:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. Minimize direct exposure to the Sun during midday when its radiation is at its peak. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Frequently asked questions
Is December cold in Grantham?
What is the average humidity in December in Grantham?
How many days does it rain in December in Grantham?
How many days does it snow in December in Grantham?
What is the month with the shortest days in Grantham?
How many hours of daylight does Grantham have in December?
What time are sunrise and sunset in December in Grantham?
How long on average sun shines in December in Grantham?
What is the month with the lowest UV index in Grantham?
What is the UV index reading in December in Grantham?
Average temperature in December
Grantham, PA
- Average high temperature in December: 41°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 (35.2°F).
- Average low temperature in December: 29.7°F
The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (22.5°F).
Average pressure in December
Grantham, 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 (29.95"Hg).
Average wind speed in December
Grantham, PA
- Average wind speed in December: 7.8mph
The windiest months (with the highest average wind speed) are February, March and April (8.4mph).
The calmest months (with the lowest average wind speed) are July and August (5mph).
Average humidity in December
Grantham, PA
- Average humidity in December: 79%
The months with the highest relative humidity are February and May (80%).
The month with the lowest relative humidity is April (75%).
Average rainfall in December
Grantham, PA
- Average rainfall in December: 1.26"
The wettest months (with the highest rainfall) are May and July (2.05").
The driest month (with the least rainfall) is January (1.14").
Average rainfall days in December
Grantham, PA
- Average rainfall days in December: 9.5 days
The month with the highest number of rainy days is May (15.6 days).
The month with the least rainy days is January (6.3 days).
Average snowfall in December
Grantham, PA
- Average snowfall in December: 1.14"
The month with the highest snowfall is January (2.52").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Grantham, PA
- Average snowfall days in December: 4.4 days
The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grantham, 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 36min).
Average sunshine days in December
Grantham, PA
- Average sunshine days in December: 18.1 days
The month with the most sunshine days is November (20 days).
The month with the least sunshine days is May (12.2 days).
Average UV index in December
Grantham, PA
- Average UV index in December: 2
The months with the highest UV index are May, June and 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
Grantham, PA
- Average cloud cover in December: 49
The months with the most cloud cover are February and December (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 30).
Average visibility in December
Grantham, 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).
Grantham, Pennsylvania, USA
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