September Weather in Killeen, United States

Last updated: June 24, 2025

In September, the average temperature in Killeen, United States hovers around 26°C (80°F). However, temperatures can vary significantly, with minimums dipping to 10°C (51°F) and maximums soaring up to 39°C (102°F). Expect some moisture as well, with 87 mm (3.4 in) of precipitation likely over about 10 days. The average humidity during this month is a comfortable 66%, making it a unique time to experience the region's climate.

September Temperature in Killeen

In September in Killeen, the average temperature is 26°C (80°F). Maximums can reach 39°C (102°F) and minimums can be as low as 10°C (51°F). Be prepared for warm days and cool nights while planning your travels!

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

The chart illustrates September temperature patterns in Killeen, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Killeen, September typically has an average temperature of 26°C (80°F), with highs reaching up to 39°C (102°F) and lows dropping to around 10°C (51°F).

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

September Precipitation in Killeen

In Killeen in September, the precipitation amount is 87 mm (3.4 in) over the course of 10 days.

September Precipitation Trends in Killeen

The chart displays monthly precipitation patterns in Killeen, 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 Killeen, September typically receives around 87 mm (3.4 inches) of precipitation spread over approximately 10 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 Killeen

In Killeen in September humidity is 66%. With an average temperature of 26°C (80°F), this humidity feels like a warm, sticky embrace, making travel a bit challenging as you might find yourself needing frequent breaks to cool down and stay hydrated.

September Average Humidity in Killeen

This chart illustrates the average monthly humidity levels in Killeen, 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 Killeen is approximately 66%, 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 Killeen

In Killeen 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 Killeen.

Maximum UV Index Levels in Killeen for September

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

Data source: Killeen 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 Killeen Compares to Other Months

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

This table compares monthly weather conditions in Killeen, 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 (50°F)	51 mm (2.0 inches)	78%	moderate
February Weather	11°C (52°F)	63 mm (2.5 inches)	78%	high
March Weather	17°C (63°F)	74 mm (2.9 inches)	77%	very high
April Weather	20°C (68°F)	84 mm (3.3 inches)	78%	very high
May Weather	24°C (76°F)	177 mm (7.0 inches)	82%	extreme
June Weather	28°C (82°F)	70 mm (2.8 inches)	78%	extreme
July Weather	30°C (86°F)	59 mm (2.3 inches)	69%	extreme
August Weather	30°C (86°F)	91 mm (3.6 inches)	63%	extreme
September Weather	26°C (80°F)	87 mm (3.4 inches)	66%	extreme
October Weather	21°C (70°F)	113 mm (4.5 inches)	73%	very high
November Weather	15°C (59°F)	39 mm (1.5 inches)	84%	high
December Weather	12°C (54°F)	55 mm (2.1 inches)	87%	moderate