September Weather in Austin, United States

Last updated: June 24, 2025

In September, the average temperature in Austin, United States is a pleasant 22°C (72°F). Expect a range of temperatures, with a minimum of 7°C (46°F) and soaring up to a maximum of 35°C (95°F). Be prepared for some rain, as 95 mm (3.7 in) of precipitation can be anticipated over 8 days. With an average humidity of 69%, it's a great time to enjoy the warm, yet comfortable climate!

September Temperature in Austin

In September in Austin, the average temperature is 22°C (72°F). Maximums can reach 35°C (95°F), while minimums can dip as low as 7°C (46°F). This variability makes it essential to pack both light clothing for the warm days and layers for cooler evenings when traveling.

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

The chart illustrates September temperature patterns in Austin, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Austin, September typically has an average temperature of 22°C (72°F), with highs reaching up to 35°C (95°F) and lows dropping to around 7°C (46°F).

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

September Precipitation in Austin

In Austin in September, the total precipitation amount is 95 mm (3.7 in) spread over 8 days.

September Precipitation Trends in Austin

The chart displays monthly precipitation patterns in Austin, 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 Austin, September typically receives around 95 mm (3.7 inches) of precipitation spread over approximately 8 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Austin

In Austin in September, humidity is 69%. With an average temperature of 22°C (72°F), this humidity feels like a warm, enveloping blanket, making travel feel sticky and slightly oppressive, yet also invigorating as the air is thick with the scent of blooming flora and vibrant surroundings.

September Average Humidity in Austin

This chart illustrates the average monthly humidity levels in Austin, 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 Austin is approximately 69%, 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 Austin

In Austin 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 Austin.

Maximum UV Index Levels in Austin for September

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

Data source: Austin 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 Austin Compares to Other Months

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

This table compares monthly weather conditions in Austin, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	1°C (34°F)	83 mm (3.3 inches)	87%	moderate
February Weather	3°C (38°F)	114 mm (4.5 inches)	85%	moderate
March Weather	8°C (47°F)	136 mm (5.4 inches)	86%	high
April Weather	13°C (55°F)	133 mm (5.3 inches)	84%	very high
May Weather	19°C (67°F)	127 mm (5.0 inches)	79%	very high
June Weather	24°C (75°F)	136 mm (5.4 inches)	82%	extreme
July Weather	26°C (78°F)	92 mm (3.6 inches)	79%	very high
August Weather	24°C (76°F)	95 mm (3.8 inches)	70%	very high
September Weather	22°C (72°F)	95 mm (3.7 inches)	69%	very high
October Weather	15°C (60°F)	97 mm (3.8 inches)	76%	high
November Weather	7°C (45°F)	94 mm (3.7 inches)	88%	moderate
December Weather	4°C (40°F)	102 mm (4.0 inches)	87%	moderate