September Weather in Collegeville, United States

Last updated: June 24, 2025

In September, the average temperature in Collegeville, United States hovers around 17°C (63°F). Expect variations with a minimum of 0°C (33°F) and a peak reaching 32°C (89°F). During this time, the region experiences 115 mm (4.5 in) of precipitation spread over about 10 days, contributing to an average humidity of 81%.

September Temperature in Collegeville

In September in Collegeville, the average temperature is 17°C (63°F), with maximums reaching 32°C (89°F) and minimums dipping as low as 0°C (33°F). This varied climate makes it essential to pack for both warm and cool conditions when traveling to Collegeville during this time.

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

The chart illustrates September temperature patterns in Collegeville, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Collegeville, September typically has an average temperature of 17°C (63°F), with highs reaching up to 32°C (89°F) and lows dropping to around 0°C (33°F).

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

September Precipitation in Collegeville

In Collegeville in September, the precipitation amount is 115 mm (4.5 in) over a span of 10 days.

September Precipitation Trends in Collegeville

The chart displays monthly precipitation patterns in Collegeville, 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 Collegeville, September typically receives around 115 mm (4.5 inches) of precipitation spread over approximately 10 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Collegeville

In Collegeville in September humidity is 81%. With an average temperature of 17°C (63°F), this humidity feels like a warm blanket enveloping you, making travel slightly oppressive and calling for frequent breaks in air-conditioned spaces to recharge and enjoy your journey comfortably.

September Average Humidity in Collegeville

This chart illustrates the average monthly humidity levels in Collegeville, 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 Collegeville is approximately 81%, 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 Collegeville

In Collegeville in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Collegeville.

Maximum UV Index Levels in Collegeville for September

The chart shows the monthly maximum UV Index (UVI) for Collegeville 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 Collegeville typically reaches 7, which falls under the high exposure category.

Data source: Collegeville 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 Collegeville Compares to Other Months

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

This table compares monthly weather conditions in Collegeville, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-10°C (15°F)	19 mm (0.8 inches)	87%	low
February Weather	-10°C (15°F)	24 mm (1.0 inches)	90%	moderate
March Weather	0°C (31°F)	50 mm (2.0 inches)	85%	moderate
April Weather	5°C (42°F)	81 mm (3.2 inches)	84%	high
May Weather	14°C (58°F)	95 mm (3.7 inches)	78%	very high
June Weather	21°C (71°F)	69 mm (2.7 inches)	80%	very high
July Weather	23°C (74°F)	98 mm (3.9 inches)	81%	very high
August Weather	21°C (70°F)	143 mm (5.6 inches)	81%	very high
September Weather	17°C (63°F)	115 mm (4.5 inches)	81%	high
October Weather	8°C (47°F)	103 mm (4.1 inches)	84%	moderate
November Weather	0°C (32°F)	29 mm (1.2 inches)	88%	moderate
December Weather	-6°C (22°F)	45 mm (1.8 inches)	84%	low