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
Stepping into December, Grassflat observes a temperature decline, with the average high falling from November's chilly 45.9°F (7.7°C) to a wintry 36.3°F (2.4°C). In December, the temperature in Grassflat drops to an average of 25.9°F (-3.4°C) at night.Humidity
In Grassflat, Pennsylvania, the average relative humidity in December is 84%.Rainfall
In Grassflat, in December, during 11.4 rainfall days, 1.57" (40mm) of precipitation is typically accumulated. In Grassflat, Pennsylvania, during the entire year, the rain falls for 159 days and collects up to 23.46" (596mm) of precipitation.Snowfall
Months with snowfall in Grassflat, Pennsylvania, are January through May, October through December. In Grassflat, in December, during 13.8 snowfall days, 4.13" (105mm) of snow is typically accumulated. Throughout the year, in Grassflat, there are 67.7 snowfall days, and 23.54" (598mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 18min of daylight.On the first day of December in Grassflat, Pennsylvania, sunrise is at 7:18 am and sunset at 4:44 pm. On the last day of the month, sunrise is at 7:37 am and sunset at 4:54 pm EST.
Sunshine
In December, the average sunshine is 3.5h.UV index
The month with the lowest UV index is December, with an average maximum UV index of 1. 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 UV index of 1 in December translates into these instructions:
Extended time in the sun generally does not harm most, but those with sensitive skin, infants, and children should always be protected. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days. Be alert to the fact! The reflection from snow can nearly double the UV radiation of the Sun.
Frequently asked questions
How cold is it in Grassflat in December?
What is the average humidity in December in Grassflat?
How much does it rain in Grassflat in December?
How many days does it snow in December in Grassflat?
What is the month with the shortest days in Grassflat?
How many hours of daylight does Grassflat have in December?
When are sunrise and sunset in December in Grassflat?
How long on average sun shines in December in Grassflat?
What is the month with the lowest UV index in Grassflat?
How high is the UV index in December in Grassflat?
Average temperature in December
Grassflat, PA
- Average high temperature in December: 36.3°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 (30.6°F).
- Average low temperature in December: 25.9°F
The month with the highest average low temperature is July (59.2°F).
The coldest month (with the lowest average low temperature) is January (18°F).
Average pressure in December
Grassflat, 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 (29.95"Hg).
Average wind speed in December
Grassflat, PA
- Average wind speed in December: 7.9mph
The windiest month (with the highest average wind speed) is January (8.5mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Grassflat, PA
- Average humidity in December: 84%
The month with the highest relative humidity is February (85%).
The month with the lowest relative humidity is July (76%).
Average rainfall in December
Grassflat, PA
- Average rainfall in December: 1.57"
The wettest month (with the highest rainfall) is May (2.87").
The driest month (with the least rainfall) is November (1.42").
Average rainfall days in December
Grassflat, PA
- Average rainfall days in December: 11.4 days
The month with the highest number of rainy days is May (17.9 days).
The month with the least rainy days is January (8.1 days).
Average snowfall in December
Grassflat, PA
- Average snowfall in December: 4.13"
The month with the highest snowfall is January (6.02").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Grassflat, PA
- Average snowfall days in December: 13.8 days
The month with the highest number of snowfall days is January (18.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grassflat, 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: 3h and 3min
The months with the most sunshine are July and August (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 24min).
Average sunshine days in December
Grassflat, PA
- Average sunshine days in December: 10.5 days
The month with the most sunshine days is September (15.4 days).
The month with the least sunshine days is February (8.7 days).
Average UV index in December
Grassflat, 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
Grassflat, PA
- Average cloud cover in December: 64
The month with the most cloud cover is January (Cloud cover 67).
The months with the least cloud cover are July and August (Cloud cover 38).
Average visibility in December
Grassflat, PA
- Average visibility in December: 5mi
The months with the highest visibility are January, March, April, May, June, July, August, October, November and December (5mi).
The months with the lowest visibility are February and September (4mi).
Grassflat, Pennsylvania, USA
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