September Weather in Boylston, United States

Last updated: June 24, 2025

In September, the average temperature in Boylston, United States hovers around 18°C (65°F), offering a pleasant climate for exploration. Expect a minimum of 3°C (38°F) and a maximum soaring to 34°C (93°F). Be prepared for occasional showers, as the area receives about 89 mm (3.5 in) of precipitation over 9 days. With an average humidity level of 71%, you're sure to feel the warmth in this vibrant locale!

September Temperature in Boylston

In September in Boylston, the average temperature is 18°C (65°F). Maximums can reach 34°C (93°F), and minimums can be as low as 3°C (38°F). This makes it a great time to explore outdoor activities while being prepared for both warm days and cooler nights.

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

The chart illustrates September temperature patterns in Boylston, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Boylston, September typically has an average temperature of 18°C (65°F), with highs reaching up to 34°C (93°F) and lows dropping to around 3°C (38°F).

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

September Precipitation in Boylston

In Boylston in September, the precipitation amount is 89 mm (3.5 in) during a span of 9 days.

September Precipitation Trends in Boylston

The chart displays monthly precipitation patterns in Boylston, 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 Boylston, September typically receives around 89 mm (3.5 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 Boylston

In Boylston in September humidity is 71%. With an average temperature of 18°C (65°F), this humidity feels like a warm embrace, making it a bit sticky and muggy, which can be slightly uncomfortable for traveling, especially if you're engaging in outdoor activities or exploring the city on foot.

September Average Humidity in Boylston

This chart illustrates the average monthly humidity levels in Boylston, 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 Boylston 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 Boylston

In Boylston 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 Boylston.

Maximum UV Index Levels in Boylston for September

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

Data source: Boylston 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 Boylston Compares to Other Months

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

This table compares monthly weather conditions in Boylston, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (28°F)	74 mm (2.9 inches)	86%	moderate
February Weather	-1°C (31°F)	90 mm (3.5 inches)	84%	moderate
March Weather	2°C (36°F)	87 mm (3.4 inches)	82%	high
April Weather	8°C (47°F)	132 mm (5.2 inches)	80%	very high
May Weather	14°C (58°F)	91 mm (3.6 inches)	72%	very high
June Weather	20°C (68°F)	93 mm (3.7 inches)	72%	very high
July Weather	23°C (73°F)	154 mm (6.1 inches)	67%	very high
August Weather	22°C (72°F)	99 mm (3.9 inches)	66%	very high
September Weather	18°C (65°F)	89 mm (3.5 inches)	71%	high
October Weather	12°C (54°F)	137 mm (5.4 inches)	78%	high
November Weather	5°C (41°F)	102 mm (4.0 inches)	84%	moderate
December Weather	0°C (32°F)	125 mm (4.9 inches)	81%	low