September Weather in Andover, United States

Last updated: June 24, 2025

In Andover, United States, the average temperature in September hovers around 20°C (69°F), with a potential minimum of 5°C (41°F) and a maximum soaring to 34°C (93°F). Expect to encounter 103 mm (4.1 in) of precipitation over approximately 9 days, contributing to an average humidity level of 78%. Enjoy the variety of weather while planning your activities!

September Temperature in Andover

In September in Andover, the average temperature is 20°C (69°F). Maximums can reach 34°C (93°F), and minimums can be as low as 5°C (41°F). This makes it a great time to visit, as you can enjoy warm days while still experiencing cooler evenings.

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

The chart illustrates September temperature patterns in Andover, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Andover, September typically has an average temperature of 20°C (69°F), with highs reaching up to 34°C (93°F) and lows dropping to around 5°C (41°F).

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

September Precipitation in Andover

In Andover in September, the precipitation amount is 103 mm (4.1 in) distributed over 9 days.

September Precipitation Trends in Andover

The chart displays monthly precipitation patterns in Andover, 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 Andover, September typically receives around 103 mm (4.1 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 Andover

In Andover in September, humidity is 78%. With an average temperature of 20°C (69°F), this humidity feels like a warm, enveloping blanket, making travel somewhat uncomfortable as sweat clings to your skin and the air feels thick and heavy, urging you to seek out shaded areas and refreshing drinks.

September Average Humidity in Andover

This chart illustrates the average monthly humidity levels in Andover, 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 Andover is approximately 78%, 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 Andover

In Andover 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 Andover.

Maximum UV Index Levels in Andover for September

The chart shows the monthly maximum UV Index (UVI) for Andover 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 Andover typically reaches 8, which falls under the very high exposure category.

Data source: Andover 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 Andover Compares to Other Months

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

This table compares monthly weather conditions in Andover, 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)	56 mm (2.2 inches)	81%	moderate
February Weather	-3°C (27°F)	63 mm (2.5 inches)	81%	moderate
March Weather	5°C (41°F)	100 mm (3.9 inches)	81%	high
April Weather	10°C (50°F)	113 mm (4.5 inches)	82%	very high
May Weather	17°C (63°F)	157 mm (6.2 inches)	78%	very high
June Weather	23°C (74°F)	143 mm (5.6 inches)	81%	extreme
July Weather	25°C (77°F)	100 mm (3.9 inches)	79%	very high
August Weather	23°C (74°F)	70 mm (2.7 inches)	77%	very high
September Weather	20°C (69°F)	103 mm (4.1 inches)	78%	very high
October Weather	12°C (55°F)	127 mm (5.0 inches)	78%	high
November Weather	4°C (39°F)	52 mm (2.0 inches)	87%	moderate
December Weather	0°C (33°F)	49 mm (1.9 inches)	84%	low