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

September 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 autumn, September, is also a moderately hot month in Harrisburg, Pennsylvania, with temperature in the range of an average high of 74.3°F (23.5°C) and an average low of 55.6°F (13.1°C).

Temperature

In September, the average high-temperature marginally drops, from 81.5°F (27.5°C) in August, to a still moderately hot 74.3°F (23.5°C). In September, in Harrisburg, the average low-temperature is 55.6°F (13.1°C).

Humidity

The average relative humidity in September is 78%.

Rainfall

In Harrisburg, it is raining for 9.7 days, with typically 0.79" (20mm) of accumulated precipitation. Throughout the year, there are 122.3 rainfall days, and 11.73" (298mm) of precipitation is accumulated.

Snowfall

In Harrisburg snow does not fall in May through October.

Daylight

In Harrisburg, the average length of the day in September is 12.4h.

Sunshine

In Harrisburg, the average sunshine is 9h.

UV index

In Harrisburg, Pennsylvania, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to the Sun's UV rays for ordinary individuals.
Note: In September, the average maximum UV index of 4 translate into the following recommendations:
Take precautions - Protection against sunburn is recommended. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. 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.

What is the temperature in September in Harrisburg?

The average high-temperature, in September, in Harrisburg, Pennsylvania, is 74.3°F (23.5°C), while the average low-temperature is 55.6°F (13.1°C).

What is the average humidity in September in Harrisburg?

The average relative humidity in September in Harrisburg is 78%.

How much does it rain in Harrisburg in September?

In September, in Harrisburg, the rain falls for 9.7 days. Throughout September, 0.79" (20mm) of precipitation is accumulated.

When it does not snow in Harrisburg?

May through October are months without snowfall in Harrisburg.

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

The average length of the day in September in Harrisburg, Pennsylvania, is 12.4h.

How long on average sun shines in September in Harrisburg?

In September, the average sunshine is 9h.

How high is the UV index in September in Harrisburg?

In Harrisburg, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health risk from the exposure to the Sun's UV radiation.
Average temperature in September - Harrisburg, PA
  • Average high temperature in September: 23.5°C

The warmest month (with the highest average high temperature) is July (28.8°C).
The month with the lowest average high temperature is January (1.7°C).

  • Average low temperature in September: 13.1°C

The month with the highest average low temperature is July (17.5°C).
The coldest month (with the lowest average low temperature) is January (-5.5°C).

Average humidity in September - Harrisburg, PA
  • Average humidity in September: 78%

The month with the highest relative humidity is February (80%).
Months with the lowest relative humidity are March and April (75%).

Average rainfall in September - Harrisburg, PA
  • Average rainfall in September: 20mm

The wettest month (with the highest rainfall) is August (33mm).
Driest months (with the lowest rainfall) are January and February (18mm).

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

The month with the highest number of rainy days is May (13.9 days).
The month with the lowest number of rainy days is January (5.7 days).

Average snowfall in September - Harrisburg, PA
  • Average snowfall in September: 0mm

The month with the highest snowfall is February (33mm).
Months with the lowest snowfall are May, June, July, August, September and October (0mm).

Average snowfall days in September - Harrisburg, PA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (6.3 days).
Months with the lowest number of snowfall days are June, July, August, September and October (0 days).

Average daylight in September / Average sunshine in September - Harrisburg, PA
  • Average daylight in September: 12.4h

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 September: 9h

The month with most sunshine is July (Average sunshine: 10.5h).
The month with least sunshine is February (Average sunshine: 4.5h).

Average UV index in September - Harrisburg, PA
  • Average UV index in September: 4

Months with the highest UV index are May, June and July (UV index 6).
Months with the lowest UV index are January, February, March, November and December (UV index 2).