September Weather in South Windham, United States

Last updated: June 24, 2025

In September, the average temperature in South Windham, United States hovers around 18°C (64°F), with minimums dipping to 4°C (39°F) and maximums soaring to 32°C (90°F). You'll experience an average humidity of 71%, along with 65 mm (2.6 in) of precipitation spread over 7 days. Prepare for a mix of conditions as you enjoy your time in this vibrant locale!

September Temperature in South Windham

In September in South Windham, the average temperature is 18°C (64°F). Maximum can reach 32°C (90°F) and minimum can be as low as 4°C (39°F). This climate makes South Windham a comfortable destination for travelers looking to enjoy a variety of outdoor activities.

September Weather in South Windham: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in South Windham, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In South Windham, September typically has an average temperature of 18°C (64°F), with highs reaching up to 32°C (90°F) and lows dropping to around 4°C (39°F).

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

September Precipitation in South Windham

In South Windham in September, the total precipitation amount is 65 mm (2.6 in) over a span of 7 days.

September Precipitation Trends in South Windham

The chart displays monthly precipitation patterns in South Windham, 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 South Windham, September typically receives around 65 mm (2.6 inches) of precipitation spread over approximately 7 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 South Windham

In South Windham in September, humidity is 71%. With an average temperature of 18°C (64°F), this humidity feels like a warm embrace, making traveling a bit sticky but still pleasant as the warmth envelops you, urging you to explore the vibrant surroundings while staying hydrated.

September Average Humidity in South Windham

This chart illustrates the average monthly humidity levels in South Windham, 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 South Windham is approximately 71%, 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 South Windham

In South Windham 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 South Windham.

Maximum UV Index Levels in South Windham for September

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

Data source: South Windham 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 South Windham Compares to Other Months

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

This table compares monthly weather conditions in South Windham, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	82 mm (3.2 inches)	86%	low
February Weather	-3°C (27°F)	90 mm (3.5 inches)	84%	moderate
March Weather	1°C (34°F)	78 mm (3.1 inches)	82%	moderate
April Weather	7°C (45°F)	120 mm (4.7 inches)	80%	high
May Weather	13°C (56°F)	73 mm (2.9 inches)	72%	very high
June Weather	19°C (66°F)	78 mm (3.1 inches)	72%	very high
July Weather	22°C (72°F)	138 mm (5.4 inches)	67%	very high
August Weather	22°C (71°F)	79 mm (3.1 inches)	66%	very high
September Weather	18°C (64°F)	65 mm (2.6 inches)	71%	high
October Weather	12°C (53°F)	126 mm (5.0 inches)	78%	moderate
November Weather	4°C (40°F)	108 mm (4.2 inches)	84%	moderate
December Weather	-1°C (30°F)	120 mm (4.7 inches)	81%	low