December weather forecast
Southwest Greensburg, PA

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Weather in December

The first month of the winter, December, is still a cold month in Southwest Greensburg, Pennsylvania, with an average temperature fluctuating between 39°F (3.9°C) and 27.9°F (-2.3°C).

Temperature

As November transitions into December, Southwest Greensburg sees a drop in the average high-temperature, transitioning from a chilly 48.7°F (9.3°C) to a cold 39°F (3.9°C). During December, the temperature is averaged to a low of 27.9°F (-2.3°C) at night.

Humidity

In Southwest Greensburg, Pennsylvania, the average relative humidity in December is 84%.

Rainfall

In Southwest Greensburg, in December, it is raining for 13.5 days, with typically 3.07" (78mm) of accumulated precipitation. Throughout the year, there are 186 rainfall days, and 34.84" (885mm) of precipitation is accumulated.

Snowfall

January through May, October through December are months with snowfall in Southwest Greensburg. In Southwest Greensburg, in December, snow falls for 12.8 days, with typically accumulated 5.67" (144mm) of snow. Throughout the year, in Southwest Greensburg, there are 63.3 snowfall days, and 27.44" (697mm) of snow is accumulated.

Daylight

December has the shortest days of the year, with an average of 9h and 24min of daylight.
On the first day of December in Southwest Greensburg, sunrise is at 7:22 am and sunset at 4:52 pm. On the last day of the month, sunrise is at 7:40 am and sunset at 5:02 pm EST.

Sunshine

In December, the average sunshine is 3.5h.

UV index

December is the month with the lowest UV index in Southwest Greensburg, with an average maximum UV index of 1. A UV Index value of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for the ordinary person.
Note: The daily high UV index of 1 during December translates into the following recommendations:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. On your guard! Snow's reflection can almost double the intensity of the Sun's UV radiation.
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Frequently asked questions

How cold is December in Southwest Greensburg?

During December, Southwest Greensburg experiences an average high-temperature of 39°F (3.9°C) and a low-temperature of 27.9°F (-2.3°C). The average heat index (a.k.a. 'apparent temperature', 'felt air temperature'), which factors the actual air temperature with the relative humidity, in August is calculated to be 86°F (30°C).

What is the average humidity in December in Southwest Greensburg?

In December, the average relative humidity in Southwest Greensburg is 84%.

How many days does it rain in December in Southwest Greensburg?

In Southwest Greensburg, Pennsylvania, in December, during 13.5 rainfall days, 3.07" (78mm) of precipitation is typically accumulated.

How many days does it snow in December in Southwest Greensburg?

In Southwest Greensburg, during December, snow falls for 12.8 days and regularly aggregates up to 5.67" (144mm) of snow.

What is the month with the shortest days in Southwest Greensburg?

The month with the shortest days in Southwest Greensburg is December, with an average of 9h and 24min of daylight.

How many hours of daylight does Southwest Greensburg have in December?

In December, the average day length in Southwest Greensburg, Pennsylvania, is 9h and 22min.

When is the sunrise / sunset in December in Southwest Greensburg?

In December, on the first day of the month, sunrise is at 7:22 am and sunset at 4:52 pm. On the last day of the month, in Southwest Greensburg, sunrise is at 7:40 am and sunset at 5:02 pm EST.

How long on average sun shines in December in Southwest Greensburg?

In December, the average sunshine duration in Southwest Greensburg, Pennsylvania, is 3.5h.

When is the lowest UV index in Southwest Greensburg?

With an average maximum UV index of 1, December is the month with the lowest UV index in Southwest Greensburg, Pennsylvania.

What is the UV index intensity in December in Southwest Greensburg?

The average daily maximum UV index in December is 1. A UV Index estimate of 2, and below, represents a low health risk from exposure to the Sun's UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Southwest Greensburg, PA

Average temperature in December - Southwest Greensburg, PA
  • Average high temperature in December: 39°F

The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (32.9°F).

  • Average low temperature in December: 27.9°F

The month with the highest average low temperature is July (60.6°F).
The coldest month (with the lowest average low temperature) is January (20.3°F).

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Average pressure in December
Southwest Greensburg, PA

Average pressure in December - Southwest Greensburg, PA
  • Average pressure in December: 30.11"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).

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Average wind speed in December
Southwest Greensburg, PA

Average wind speed in December - Southwest Greensburg, 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 (4.8mph).

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Average humidity in December
Southwest Greensburg, PA

Average humidity in December - Southwest Greensburg, PA
  • Average humidity in December: 84%

The months with the highest relative humidity are January and February (85%).
The months with the lowest relative humidity are April, July and August (77%).

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Average rainfall in December
Southwest Greensburg, PA

Average rainfall in December - Southwest Greensburg, PA
  • Average rainfall in December: 3.07"

The wettest month (with the highest rainfall) is May (3.74").
The driest month (with the least rainfall) is November (2.01").

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Average rainfall days in December
Southwest Greensburg, PA

Average rainfall days in December - Southwest Greensburg, PA
  • Average rainfall days in December: 13.5 days

The month with the highest number of rainy days is May (20.9 days).
The month with the least rainy days is January (9.8 days).

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Average snowfall in December
Southwest Greensburg, PA

Average snowfall in December - Southwest Greensburg, PA
  • Average snowfall in December: 5.67"

The month with the highest snowfall is January (6.65").
The months with the least snowfall are June, July, August and September (0").

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Average snowfall days in December
Southwest Greensburg, PA

Average snowfall days in December - Southwest Greensburg, PA
  • Average snowfall days in December: 12.8 days

The month with the highest number of snowfall days is January (17.6 days).
The months with the least snowfall days are June, July, August and September (0 days).

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Average daylight in December /
Average sunshine in December
Southwest Greensburg, PA

Average daylight in December / Average sunshine in December - Southwest Greensburg, 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: 3h and 3min

The month with the most sunshine is August (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 0min).

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Average sunshine days in December
Southwest Greensburg, PA

Average sunshine days in December - Southwest Greensburg, PA
  • Average sunshine days in December: 8.8 days

The month with the most sunshine days is November (13.5 days).
The month with the least sunshine days is January (6.4 days).

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Average UV index in December
Southwest Greensburg, PA

Average UV index in December - Southwest Greensburg, PA
  • Average UV index in December: 1

The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).

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Average cloud cover in December
Southwest Greensburg, PA

Average cloud cover in December - Southwest Greensburg, PA
  • Average cloud cover in December: 65

The month with the most cloud cover is January (Cloud cover 70).
The month with the least cloud cover is August (Cloud cover 35).

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Average visibility in December
Southwest Greensburg, PA

Average visibility in December - Southwest Greensburg, PA
  • Average visibility in December: 5mi

The month with the highest visibility is April (6mi).
The months with the lowest visibility are January and February (4mi).

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Southwest Greensburg, Pennsylvania, USA

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