September Weather in Grafton, United States

Last updated: June 24, 2025

In Grafton, United States, the average temperature in September hovers around 17°C (62°F). Expect a wide range, with minimums dipping to -2°C (28°F) and maximums soaring to 32°C (89°F). During this period, anticipate approximately 65 mm (2.6 in) of precipitation spread over 8 days, accompanied by an average humidity of 71%.

September Temperature in Grafton

In September in Grafton, the average temperature is 17°C (62°F), with maximums reaching up to 32°C (89°F) and minimums plummeting as low as -2°C (28°F). Travelers should be prepared for a wide range of temperatures during this month.

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

The chart illustrates September temperature patterns in Grafton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Grafton, September typically has an average temperature of 17°C (62°F), with highs reaching up to 32°C (89°F) and lows dropping to around -2°C (28°F).

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

September Precipitation in Grafton

In Grafton in September, the total precipitation amount is 65 mm (2.6 in) spread over the course of 8 days.

September Precipitation Trends in Grafton

The chart displays monthly precipitation patterns in Grafton, 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 Grafton, September typically receives around 65 mm (2.6 inches) of precipitation spread over approximately 8 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 Grafton

In Grafton in September, humidity is 71%. With an average temperature of 17°C (62°F), this humidity feels like a warm embrace that can leave you feeling a bit sticky, making outdoor exploration both refreshing and slightly uncomfortable.

September Average Humidity in Grafton

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

In Grafton 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 Grafton.

Maximum UV Index Levels in Grafton for September

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

Data source: Grafton 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 Grafton Compares to Other Months

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

This table compares monthly weather conditions in Grafton, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-6°C (22°F)	70 mm (2.8 inches)	86%	moderate
February Weather	-4°C (25°F)	82 mm (3.2 inches)	84%	moderate
March Weather	0°C (32°F)	75 mm (2.9 inches)	82%	moderate
April Weather	6°C (44°F)	121 mm (4.8 inches)	80%	very high
May Weather	13°C (56°F)	83 mm (3.3 inches)	72%	very high
June Weather	19°C (66°F)	91 mm (3.6 inches)	72%	very high
July Weather	22°C (71°F)	125 mm (4.9 inches)	67%	very high
August Weather	21°C (69°F)	89 mm (3.5 inches)	66%	very high
September Weather	17°C (62°F)	65 mm (2.6 inches)	71%	high
October Weather	10°C (50°F)	129 mm (5.1 inches)	78%	moderate
November Weather	2°C (36°F)	106 mm (4.2 inches)	84%	moderate
December Weather	-3°C (26°F)	109 mm (4.3 inches)	81%	low