Harrisburg
Pennsylvania, USA
Long-term weather forecast
Long-term weather forecast

December weather forecast and climate
Harrisburg, PA

A church, a mosque, and other buildings along State Street in Harrisburg, Pennsylvania
A church, a mosque, and other buildings along State Street in Harrisburg, Pennsylvania
The first month of the winter, December, is still a cold month in Harrisburg, Pennsylvania, with average temperature varying between 26.6°F (-3°C) and 41.4°F (5.2°C).

Temperature

In Harrisburg, the average high-temperature drops, from a fresh 53.1°F (11.7°C) in November, to a cold 41.4°F (5.2°C). In Harrisburg, in December, the average low-temperature is 26.6°F (-3°C).

Humidity

The average relative humidity in Harrisburg is 66.4%.

Rainfall

In Harrisburg, Pennsylvania, it is raining for 9.7 days, with typically 3.2" (82mm) of accumulated precipitation. Throughout the year, there are 122 rainfall days, and 40.7" (1034.8mm) of precipitation is accumulated.

Snowfall

Months with snowfall in Harrisburg are January through April, November and December. In December, in Harrisburg, it is snowing for 2.8 days. Throughout December, 5.1" (129.5mm) of snow is accumulated. In Harrisburg, during the entire year, snow falls for 16.8 days, and aggregates up to 30.6" (777.2mm) of snow.

Daylight

The month with the shortest days in Harrisburg is December, with an average of 9.4h of daylight.

Sunshine

With an average of 4.1h of sunshine, December has the least sunshine of the year in Harrisburg, Pennsylvania.

UV index

January, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to the UV radiation for ordinary individuals.
Note: The average daily UV index of 2 transform into the following instructions:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the temperature in December in Harrisburg?

The average high-temperature, in December, is 41.4°F (5.2°C), while the average low-temperature is 26.6°F (-3°C).

What is the average humidity in December in Harrisburg?

The average relative humidity in December in Harrisburg, Pennsylvania, is 66.4%.

How much does it rain in Harrisburg in December?

In December, in Harrisburg, the rain falls for 9.7 days. Throughout December, 3.2" (82mm) of precipitation is accumulated.

How many days does it snow in December in Harrisburg?

In December, in Harrisburg, Pennsylvania, it is snowing for 2.8 days. Throughout December, 5.1" (129.5mm) of snow is accumulated.

What is the month with the shortest days in Harrisburg?

December has the shortest days of the year in Harrisburg, with an average of 9.4h of daylight.

What is the average length of the day in December in Harrisburg?

The average length of the day in December in Harrisburg is 9.4h.

What is the month with the least sunshine in Harrisburg?

With an average of 4.1h of sunshine, December has the least sunshine of the year in Harrisburg, Pennsylvania.

How long on average sun shines in December in Harrisburg?

The average sunshine in December is 4.1h.

What is the month with the lowest UV index in Harrisburg?

Months with the lowest UV index in Harrisburg, Pennsylvania, are January, November and December, with an average maximum UV index of 2.

How high is the UV index in December in Harrisburg?

In Harrisburg, Pennsylvania, the average daily maximum UV index in December is 2. A UV Index reading of 2, and below, represents a minimal hazard to health from the exposure to the Sun's UV radiation.
Average temperature in December - Harrisburg, PA
  • Average high temperature in December: 41.3°F

The warmest month (with the highest average high temperature) is July (85.5°F).
The month with the lowest average high temperature is January (37°F).

  • Average low temperature in December: 26.6°F

The month with the highest average low temperature is July (66.3°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).

Average humidity in December - Harrisburg, PA
  • Average humidity in December: 66.4%

The month with the highest relative humidity is September (73.8%).
The month with the lowest relative humidity is April (59.2%).

Average rainfall in December - Harrisburg, PA
  • Average rainfall in December: 3.2"

The wettest month (with the highest rainfall) is July (4.6").
The driest month (with the lowest rainfall) is February (2.4").

Average rainfall days in December - Harrisburg, PA
  • Average rainfall days in December: 9.7 days

The month with the highest number of rainy days is May (12.2 days).
The month with the lowest number of rainy days is October (8.8 days).

Average snowfall in December - Harrisburg, PA
  • Average snowfall in December: 5.1"

The month with the highest snowfall is February (10.5").
Months with the lowest snowfall are May, June, July, August, September and October (0").

Average snowfall days in December - Harrisburg, PA
  • Average snowfall days in December: 2.8 days

The month with the highest number of snowfall days is January (5.2 days).
Months with the lowest number of snowfall days are May, June, July, August, September and October (0 days).

Average daylight in December / Average sunshine in December - Harrisburg, PA
  • Average daylight in December: 9.4h

The month with the longest days is June (Average daylight: 15h).
The month with shortest days is December (Average daylight: 9.4h).

  • Average sunshine in December: 4.1h

The month with most sunshine is July (Average sunshine: 10h).
The month with least sunshine is December (Average sunshine: 4.1h).

Average UV index in December - Harrisburg, PA
  • Average UV index in December: 2

Months with the highest UV index are June and July (UV index 9).
Months with the lowest UV index are January, November and December (UV index 2).