September Weather in Boerne, United States

Last updated: June 24, 2025

In Boerne, United States, the average temperature in September reaches a pleasant 26°C (78°F). However, be prepared for a wide temperature range, with minimums dipping to 10°C (51°F) and soaring highs of 38°C (101°F). Expect around 118 mm (4.7 in) of precipitation spread over 11 days, contributing to an average humidity of 65%. Stay in tune with the weather to make the most of your time here!

September Temperature in Boerne

In September, in Boerne, the average temperature is 26°C (78°F). Maximum temperatures can reach 38°C (101°F), while the minimum can drop as low as 10°C (51°F). This comfortable climate makes it an ideal destination for travelers seeking both warmth and cooler evenings to enjoy.

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

The chart illustrates September temperature patterns in Boerne, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Boerne, September typically has an average temperature of 26°C (78°F), with highs reaching up to 38°C (101°F) and lows dropping to around 10°C (51°F).

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

September Precipitation in Boerne

In Boerne in September, the precipitation amount is 118 mm (4.7 in) over the course of 11 days.

September Precipitation Trends in Boerne

The chart displays monthly precipitation patterns in Boerne, 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 Boerne, September typically receives around 118 mm (4.7 inches) of precipitation spread over approximately 11 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 Boerne

In Boerne in September, humidity is 65%. With an average temperature of 26°C (78°F), this humidity feels like a warm, muggy embrace that can make outdoor activities a bit challenging, often leaving travelers feeling sticky and in need of frequent breaks in the shade.

September Average Humidity in Boerne

This chart illustrates the average monthly humidity levels in Boerne, 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 Boerne is approximately 65%, 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 Boerne

In Boerne in September, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Boerne.

Maximum UV Index Levels in Boerne for September

The chart shows the monthly maximum UV Index (UVI) for Boerne 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 Boerne typically reaches 11, which falls under the extreme exposure category.

Data source: Boerne 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 Boerne Compares to Other Months

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

This table compares monthly weather conditions in Boerne, 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 (51°F)	45 mm (1.8 inches)	79%	moderate
February Weather	12°C (53°F)	57 mm (2.3 inches)	79%	very high
March Weather	17°C (63°F)	65 mm (2.6 inches)	74%	very high
April Weather	20°C (68°F)	75 mm (2.9 inches)	76%	extreme
May Weather	24°C (75°F)	135 mm (5.3 inches)	81%	extreme
June Weather	27°C (81°F)	84 mm (3.3 inches)	76%	extreme
July Weather	28°C (83°F)	58 mm (2.3 inches)	66%	extreme
August Weather	29°C (84°F)	58 mm (2.3 inches)	58%	extreme
September Weather	26°C (78°F)	118 mm (4.7 inches)	65%	extreme
October Weather	21°C (70°F)	84 mm (3.3 inches)	74%	very high
November Weather	15°C (59°F)	40 mm (1.6 inches)	81%	high
December Weather	12°C (54°F)	53 mm (2.1 inches)	86%	moderate