Last updated: February 24, 2025
September in Austin, United States, showcases a unique blend of warmth and humidity. With maximum temperatures soaring to 38°C (101°F) and an average of 27°C (80°F), the month invites outdoor activities despite occasional cooling spells with a minimum of 11°C (52°F). Rainfall is a regular feature, with 113 mm (4.5 in) of precipitation spread over 11 days, creating a lush backdrop for the city's vibrant atmosphere. The humidity level remains at a sticky 66%, making it essential for residents and visitors alike to stay hydrated while enjoying the sultry September days.
In September, Austin transitions from the sweltering heat of summer to the more moderate temperatures of fall. The month showcases a minimum temperature of 11°C (52°F), with an average that pleasantly lingers around 27°C (80°F), peaking at a sweltering 38°C (101°F). This trend highlights a gradual cooling as the days become shorter and summer's intensity wanes. With an average temperature just shy of late summer highs, September serves as a bridge, allowing residents to enjoy the lingering warmth while hinting at the refreshing crispness of autumn just around the corner. Whether basking in the sun or anticipating cooler evenings, September in Austin offers a dynamic blend of summer's charm and fall's promise.
As September unfolds in Austin, it continues to embrace the lingering warmth of summer while experiencing a notable increase in rainfall. With 113 mm (4.5 in) of precipitation over 11 days, this month marks a slight dip from the wetter months of May and August but remains one of the more substantial periods for rainfall. The trend shows that as the year progresses, particularly from the scorching summer, there’s a pattern of rising precipitation that peaks in May and gradually tapers off into the autumn months. September's rainfall serves as a vital transition, preparing the landscape for the drier fall months ahead. This blend of warmth and moisture fosters a vibrant ecosystem, showcasing the resilience of nature in this dynamic climate.
As summer fades into fall, September in Austin brings a noticeable shift in humidity levels. With an average of 66% humidity, the air feels much more comfortable compared to the sweltering months of July and August, which see lower averages of 69% and 63%, respectively. This slight uptick in moisture heralds the upcoming transition to the wetter fall months, contrasting with the more humid spring and early summer. Interestingly, September serves as a bridge in Austin's humidity trend, embodying a period of relief as residents enjoy the gradual cooling while still savoring the lingering warmth of late summer.
In September, Austin experiences a UV Index of 10, categorized as very high, which indicates a sun exposure risk that warrants caution. Following the intense summer months of July and August, which both reached an extreme UV Index of 12, September marks a slight dip, yet the burn time remains relatively short at 15 minutes. This trend highlights the persistent need for sun protection even as the seasons begin to shift. As the days grow shorter and temperatures cool, residents should still stay vigilant against UV radiation. For more detailed information on the UV Index throughout the year, check out Austin UV Index.
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As summer fades into autumn, September in Austin continues to bask in a generous 276 hours of sunshine, slightly less than the sizzling peak of July's 350 hours. This transition marks a dip from the intense heat of summer while still offering ample sunlight perfect for outdoor activities. With a gradual decline as the year progresses, September's sunlight is just shy of the vibrant hues of May, which boasts 282 hours. This month serves as a gentle reminder of summer's lingering warmth before the shorter, cooler days of fall take hold, making it an ideal time for Austinites to soak up the remaining rays before the pace of the year shifts towards winter.
As September rolls into Austin, the likelihood of sunny weather emerges as a highlight of the month, with a notable 59% chance of sunshine. This trend marks a delightful shift from the earlier summer months, where the sun was less dependable, with probabilities dipping as low as 29% in May and 33% in July. Interestingly, September's sunshine potential rivals that of January and November, both sitting at 59%, suggesting that as summer fades, the weather remains vibrant and inviting. This makes September a prime time for outdoor activities, where residents and visitors alike can bask in the warmth before the cooler autumn days set in.
As the sweltering heat of summer gives way to the gentle embrace of autumn, September in Austin marks a subtle transition in daylight duration. With 12 hours of daylight, the month continues the trend of longer days seen through the summer, but signals the beginning of shorter daylight as we approach fall. Following the peak 14 hours in June, daylight hours begin their gradual decline. This shift hints at the cozy, cooler days ahead, inviting residents to savor the golden early evenings. The balance of light and shadow during September makes it a perfect time for outdoor activities, as Austinites enjoy one last taste of summer's bounty before nature transitions into the rich, vibrant hues of autumn.
As September rolls into Austin, the winds take on a gentle character, averaging 2.7 m/s (6 mph), a slight dip from the summer months. Following the trend of decreasing wind speeds throughout the hotter months, September's breezes are softer than those in earlier spring, where gusts were notably stronger at 4.3 m/s (10 mph) in March. This transition marks the beginning of a shift towards the crisp, more brisk winds of autumn, hinting at the upcoming change in seasons. While the winds may be calm, they carry with them the promise of cooler days ahead, inviting residents to enjoy the outdoors before the fall chill sets in.
The weather in Austin changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Austin and find detailed weather information for every month.
September and January offer strikingly different weather patterns. In September, temperatures soar with a minimum of 11°C (52°F) and an average high of 27°C (80°F), reaching up to 38°C (101°F), while humidity sits at a moderate 66%. Additionally, this month receives about 113 mm (4.5 inches) of precipitation over 11 days, making it a relatively wet month. In contrast, January brings much colder temperatures, with lows plummeting to -8°C (17°F) and a more temperate average of 11°C (52°F); the highs reach a milder 27°C (81°F). Additionally, January experiences significantly less precipitation, totaling 49 mm (1.9 inches) over just six days and higher humidity at 78%. For a deeper look into the January climate, you can check out Austin weather in January.
September and February present starkly contrasting weather patterns. In September, temperatures range from a mild 11°C (52°F) at night to a scorching 38°C (101°F) during the day, with an average of 27°C (80°F). The month experiences considerable rainfall, totaling 113 mm (4.5 in) over about 11 days, accompanied by a moderate humidity of 66%. In contrast, February showcases a much cooler climate, with nighttime lows plummeting to -15°C (5°F) and daytime highs reaching a comfortable 31°C (88°F). The month sees less precipitation, occurring on about 9 days and totaling 58 mm (2.3 in), but it holds higher humidity levels at 78%. For more specific details about February's weather, you can refer to Austin weather in February.
September and March exhibit distinct weather characteristics. In September, temperatures can soar, with averages around 27°C (80°F) and a maximum reaching up to 38°C (101°F), while the minimum stays comfortable at 11°C (52°F). However, September also brings considerable humidity at 66% and notable precipitation, totaling 113 mm (4.5 in) over approximately 11 days. In contrast, March presents a cooler and more varied climate, with average temperatures around 18°C (64°F) and maximums of 33°C (91°F), while the minimum can drop to -3°C (26°F). Moreover, March experiences less rainfall, 69 mm (2.7 in) over about 10 days, along with a slightly higher humidity level at 77%. For more detailed information, check out Austin weather in March.
September and April present contrasting weather conditions, each with its unique characteristics. In September, temperatures can soar with a minimum of 11°C (52°F) and reaching highs of up to 38°C (101°F), averaging around 27°C (80°F). This month also experiences significant rainfall, accumulating 113 mm (4.5 in) over about 11 days, contributing to a moderate humidity level of 66%. In contrast, April offers cooler temperatures, with a minimum of 4°C (39°F) and a comfortable average of 20°C (69°F), peaking at 35°C (96°F). The month sees slightly less rainfall at 90 mm (3.5 in) over 9 days, but with higher humidity at 78%. For more detailed information, you can visit Austin weather in April.
When comparing the weather in September and May, both months exhibit warm temperatures, but September tends to be slightly hotter overall. In September, average temperatures reach around 27°C (80°F), peaking at a maximum of 38°C (101°F), while May has a slightly lower average of 25°C (77°F) with a maximum of 37°C (99°F). Precipitation is higher in May, with 155 mm (6.1 in) of rain falling over 13 days compared to September's 113 mm (4.5 in) over 11 days. Additionally, humidity levels are notably higher in May at 82%, compared to September's 66%. For more detailed information about the conditions during this month, you can check Austin weather in May.
When comparing the weather in September and June, several key differences emerge. September experiences a broader range of temperatures, with a minimum of 11°C (52°F) and a maximum that matches June at 38°C (101°F), while the average temperature is slightly lower at 27°C (80°F) compared to June's 28°C (82°F). Additionally, September has higher precipitation levels of 113 mm (4.5 in) over 11 days, compared to June’s 98 mm (3.8 in) over 10 days, indicating a wetter end of summer. The humidity in June is also notably higher at 78%, compared to September's 66%, resulting in a more comfortable atmosphere as the month progresses. For more detailed information, you can check Austin weather in June.
In comparing the weather of September and July, it’s clear that September offers a slightly wider temperature range, with minimums of 11°C (52°F) compared to July's warmer minimum of 17°C (64°F). The average temperatures in both months are relatively close, with September averaging 27°C (80°F) and July averaging 29°C (85°F). However, July experiences more extreme heat with a maximum temperature of 42°C (108°F) versus September's maximum of 38°C (101°F). In terms of precipitation, September is wetter, receiving 113 mm (4.5 in) over 11 days compared to July’s 71 mm (2.8 in) across 8 days. Both months maintain high humidity levels, with July at 69% and September slightly lower at 66%. For more detailed insights, check out Austin weather in July.
In comparing the weather between August and September, September tends to be slightly cooler with average temperatures ranging from a minimum of 11°C (52°F) to a maximum of 38°C (101°F), while August experiences higher temperatures, with a minimum of 20°C (68°F) and a peak of 41°C (105°F). Precipitation levels are fairly similar, with September receiving 113 mm (4.5 in) over 11 days compared to August's 118 mm (4.6 in) over just 7 days. Additionally, September has a higher humidity level at 66%, making the weather feel a bit more muggy despite the lower temperatures. For more details about August weather, visit Austin weather in August.
In September, the weather is characterized by warmer temperatures, with a minimum of 11°C (52°F), an average of 27°C (80°F), and a maximum reaching up to 38°C (101°F). This month sees significant rainfall, with 113 mm (4.5 in) occurring over 11 days, and humidity levels sitting at 66%. In contrast, October brings a notable drop in temperature, with a minimum of 3°C (37°F) and an average high of 21°C (71°F), peaking at 36°C (97°F). Although it is slightly drier with 95 mm (3.7 in) of precipitation over 9 days, the humidity rises to 73%, making it feel a bit more muggy. For more details on what to expect, check Austin weather in October.
September and November exhibit starkly contrasting weather patterns. In September, temperatures can soar with an average high of 27°C (80°F), peaking at a sweltering 38°C (101°F). The month tends to experience considerable rainfall, with a total of 113 mm (4.5 in) spread over 11 days and a relatively moderate humidity level of 66%. Conversely, November brings a dramatic drop in temperatures, with an average high of just 15°C (60°F) and minimums dipping as low as -3°C (26°F). Precipitation decreases as well, totaling 52 mm (2.0 in) over merely 6 days, and humidity rises to a higher 84%. For a more detailed look at Austin's weather in November, you can check this link: Austin weather in November.
In September, the weather is quite warm, with average temperatures around 27°C (80°F) and maximums reaching up to 38°C (101°F). The month sees significant rainfall, with 113 mm (4.5 inches) of precipitation over about 11 days, and humidity levels averaging 66%. In contrast, December brings much cooler conditions, with average temperatures dropping to 13°C (55°F) and nighttime lows that can dip to -3°C (27°F). Rainfall decreases as well, totaling 78 mm (3.1 inches) over just 6 days, although humidity rises to 87%. For a more detailed look at the weather conditions in December, check out Austin weather in December.
As summer begins to wane, September in Austin brings a welcome shift in weather patterns. The month showcases warmer days, with occasional peaks that flirt with the heat of summer, yet cooler evenings invite a refreshing respite. With moderate humidity and a notable increase in precipitation days, it marks a transition toward the upcoming fall. Although the rainfall can be a bit disruptive, it nourishes the city’s vibrant greenery, setting the stage for autumn’s beauty. For more insights on how this month compares to others in the area, visit Austin Climate.