September Weather in Mechanicsburg, United States

Last updated: June 24, 2025

In September, the average temperature in Mechanicsburg, United States is a pleasant 21°C (69°F), with daytime highs reaching up to 34°C (94°F) and occasional dips to a cool 5°C (41°F). Expect about 116 mm (4.6 in) of precipitation over 9 days, contributing to an average humidity level of 66%. Enjoy the varied climate this month brings!

September Temperature in Mechanicsburg

In September in Mechanicsburg, the average temperature is 21°C (69°F), with maximums reaching 34°C (94°F) and minimums dropping as low as 5°C (41°F). This makes it a great time for travelers to enjoy a variety of outdoor activities while being prepared for some temperature fluctuations.

September Weather in Mechanicsburg: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Mechanicsburg, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Mechanicsburg, September typically has an average temperature of 21°C (69°F), with highs reaching up to 34°C (94°F) and lows dropping to around 5°C (41°F).

Data source: Temperature data for Mechanicsburg generated using information from the Copernicus Climate Change Service.

September Precipitation in Mechanicsburg

In Mechanicsburg in September, the precipitation amount is 116 mm (4.6 in) spread over 9 days.

September Precipitation Trends in Mechanicsburg

The chart displays monthly precipitation patterns in Mechanicsburg, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Mechanicsburg, September typically receives around 116 mm (4.6 inches) of precipitation spread over approximately 9 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Mechanicsburg

In Mechanicsburg in September humidity is 66%. With an average temperature of 21°C (69°F), this humidity feels like a warm embrace, making it a bit sticky, but still comfortable for traveling as long as you stay hydrated and take breaks in the shade.

September Average Humidity in Mechanicsburg

This chart illustrates the average monthly humidity levels in Mechanicsburg, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Mechanicsburg is approximately 66%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Mechanicsburg

In Mechanicsburg in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Mechanicsburg.

Maximum UV Index Levels in Mechanicsburg for September

The chart shows the monthly maximum UV Index (UVI) for Mechanicsburg in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Mechanicsburg typically reaches 8, which falls under the very high exposure category.

Data source: Mechanicsburg September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Mechanicsburg Compares to Other Months

Weather in Mechanicsburg varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Mechanicsburg, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Mechanicsburg, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	1°C (34°F)	64 mm (2.5 inches)	87%	moderate
February Weather	3°C (37°F)	99 mm (3.9 inches)	85%	moderate
March Weather	6°C (43°F)	94 mm (3.7 inches)	85%	high
April Weather	12°C (53°F)	102 mm (4.0 inches)	83%	very high
May Weather	17°C (63°F)	121 mm (4.8 inches)	75%	very high
June Weather	22°C (72°F)	92 mm (3.6 inches)	73%	very high
July Weather	25°C (78°F)	132 mm (5.2 inches)	65%	very high
August Weather	24°C (76°F)	107 mm (4.2 inches)	62%	very high
September Weather	21°C (69°F)	116 mm (4.6 inches)	66%	very high
October Weather	15°C (59°F)	105 mm (4.1 inches)	79%	high
November Weather	7°C (45°F)	86 mm (3.4 inches)	87%	moderate
December Weather	3°C (38°F)	88 mm (3.5 inches)	85%	low