Last updated: August 21, 2025
September in São Paulo, Brazil ushers in the transition from winter to spring, showcasing an appealing range of temperatures. The maximum temperature can soar to 35°C (95°F), while the average hovers around a comfortable 20°C (69°F), dipping to a cool minimum of 9°C (48°F) during the night. Although the month experiences light precipitation, with about 40 mm (1.6 in) spread over six days, the humidity sits at a pleasant 58%, contributing to the city's vibrant atmosphere. This combination of warmth and occasional rain brings life back to the lush landscapes of São Paulo, making it an inviting time to explore the city.
In September, São Paulo begins to shake off the winter chill, welcoming a gradual rise in temperatures. With a minimum of 9°C (48°F) and an average of 20°C (69°F), the city experiences a refreshing transition as the days warm up. This month can be particularly warm, peaking at 35°C (95°F), which is a noticeable jump compared to the cooler months preceding it. The overall trend reflects a shift from cooler, austere winter temperatures to the vibrant warmth of spring, inviting both residents and visitors alike to enjoy the sun-drenched streets and blossoming parks that characterize this delightful season in Brazil's bustling metropolis.
In September, São Paulo experiences a noticeable shift in its precipitation patterns, with 40 mm (1.6 in) of rain falling over 6 days. This marks a slight uptick from the drier months of July and August, when rainfall was scarce, plunging to 25 mm (1.0 in) and 57 mm (2.2 in) respectively. As the city approaches the wetter months ahead, September's relatively modest rainfall serves as a gentle precursor to the more substantial deluges of October and November, which typically bring averages of 118 mm (4.6 in) and 116 mm (4.6 in). This gradual increase in precipitation hints at the onset of the spring season in Brazil, setting the stage for a lush and vibrant landscape as the region prepares for the coming rains.
As the year progresses in São Paulo, Brazil, September marks a notable transition in humidity levels. With humidity dropping to 58%, this month enjoys a refreshing respite from the high humidity that dominates the earlier months, particularly January and February, which consistently hover around a muggy 88%. The gradual decrease throughout the winter months culminates in September, where relative dryness begins to set in, paving the way for October's even lower levels of 50% humidity. This trend highlights São Paulo's shift from the oppressive summer conditions to more comfortable, breezy days—making September an ideal time to explore the city's vibrant outdoor offerings. As the humidity begins to rise again into the spring months, São Paulo residents and visitors alike can relish the pleasant change in the atmosphere.
As the seasons shift in September, Sao Paulo's UV Index remains notably high, recorded at 11, categorizing it as extreme with a burn time of just 10 minutes. This marks a slight increase from August's UV Index of 9, which indicates a transition back to more potent sun exposure as the city moves towards the peak summer months. Following the trend of recent months, the city's UV Index remains consistent with the extreme levels seen earlier in the year, highlighting the need for sun protection during outdoor activities. As you navigate this vibrant metropolis, be sure to stay informed on the UV trends; for more details, visit Sao Paulo UV Index.
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As the warm days of September unfold in São Paulo, the city basks in approximately 294 hours of radiant sunshine, reflecting a delightful transition from the colder months. This period maintains a consistent brightness comparable to the previous summer months, such as January and March, which boast impressive totals of 245 and 310 hours, respectively. Following the mild winter, September’s sunshine heralds the arrival of spring, with daylight hours gradually increasing along with the vibrant energy of the city. Interestingly, the sunshine trend continues upward as the year progresses, suggesting that São Paulo delights in an abundance of sunlight, especially as it approaches the blissful summer months ahead.
When considering the likelihood of sunny weather in September in São Paulo, Brazil, noteworthy trends emerge. September enjoys a moderate chance of sunshine at 43%, closely mirroring the optimism of April and slightly lower than the sun-drenched July, which boasts the highest chance at 57%. As the city transitions from the dry winter months, August's 48% chance sets the stage for September's promising forecast, before dipping again into the clouds in the subsequent months of October and November. Thus, September stands as a delightful bridge, offering a blend of sunshine before the more overcast days of late spring.
As the seasons shift in São Paulo, September marks a delightful transition with 11 hours of daylight. This duration reflects a stabilization after the longer days of summer and the consistent decrease seen from January’s peak of 13 hours. Following a gradual taper over the spring months, September's sunshine offers a comforting balance as daylight starts to increase again leading into the warmer days of October and November. The city's residents can relish in the moderate lengths of day, enjoying outdoor activities as daylight begins to regain its foothold before the final stretch of the year.
As September unfolds in São Paulo, the city experiences a refreshing shift in its winds, with average speeds reaching 3.3 m/s (7 mph). This slight uptick from the previous months signals a transition towards stronger breezes, a trend that continues into October. August's winds set the stage with an average of 3.2 m/s (7 mph), marking the beginning of a seasonal change. Throughout the year, wind speeds generally oscillate between 2.1 m/s and 3.6 m/s, but September stands out, hinting at the approaching spring with its invigorating gusts. As the city breathes in the crisper air, these lively winds bring a sense of renewal, encouraging residents to embrace the vibrant energy of the season ahead.
Weather in Sao Paulo varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Sao Paulo, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather in Sao Paulo presents a mild climate, with temperatures ranging from a cool 9°C (48°F) at night to a warm 35°C (95°F) during the day. The average temperature hovers around 20°C (69°F), accompanied by relatively low precipitation of 40 mm (1.6 in) over about 6 days, resulting in a humidity level of 58%.
Conversely, January features warmer temperatures, with lows around 15°C (59°F), highs reaching 34°C (93°F), and an average of 23°C (74°F). This month is markedly wetter, receiving 177 mm (7.0 in) of rain over approximately 20 days and a significantly higher humidity of 88%. This stark contrast illustrates how September offers a drier, more moderate climate compared to the humid and rainy conditions typical of January. For further details, you can check out Sao Paulo weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a minimum of 9°C to a maximum of 35°C, with an average of 20°C. The month typically experiences around 40 mm of precipitation over about 6 days, accompanied by a humidity level of 58%. In stark contrast, February boasts milder minimum temperatures of 15°C and an average of 23°C, while still reaching highs of 35°C. However, it brings significantly more rainfall, with 158 mm spread across 17 days, resulting in much higher humidity at 88%. For a detailed look at what to expect, check out Sao Paulo weather in February.
September typically brings milder temperatures, with an average of 20°C (69°F) and daytime highs reaching up to 35°C (95°F). In contrast, March sees slightly warmer average temperatures of around 23°C (73°F), with highs of 33°C (91°F). However, March tends to be much wetter, receiving 135 mm (5.3 in) of rain across 16 days, compared to just 40 mm (1.6 in) over 6 days in September. Additionally, humidity levels are higher in March at 87%, compared to 58% in September. For more detailed insights, check out Sao Paulo weather in March.
September and April exhibit distinct weather patterns in terms of temperature and precipitation. In September, temperatures can range from a minimum of 9°C (48°F) to a maximum of 35°C (95°F), with an average of 20°C (69°F). The month experiences about 40 mm (1.6 in) of rainfall over approximately six days, along with a humidity level of 58%. Conversely, April showcases slightly warmer minimum temperatures at 11°C (52°F) and a lower maximum of 31°C (89°F), while maintaining the same average of 20°C (69°F). This month sees increased precipitation, totaling 55 mm (2.2 in) over around nine days and a higher humidity rate of 84%. For more detailed weather insights, you can check Sao Paulo weather in April.
In comparing the weather of September and May, we notice notable differences in temperature and humidity. September offers a wider temperature range, with minimums reaching 9°C (48°F) and maximums as high as 35°C (95°F), providing a more summery feel. In contrast, May features cooler temperatures with minimums of 5°C (42°F) and maximums capped at 29°C (85°F). Interestingly, while May sees slightly more precipitation at 48 mm (1.9 in) over the same number of rainy days as September, the humidity is noticeably higher in May at 79% compared to September's 58%. For further insights on May weather, check out Sao Paulo weather in May.
When comparing the weather in September and June, September generally offers warmer temperatures, with an average of 20°C (69°F) and a maximum reaching 35°C (95°F), compared to June's average of 18°C (64°F) and a maximum of 28°C (82°F). Both months experience around 40 to 45 mm of precipitation over six days, but June tends to be more humid with a humidity level of 77%, compared to September's 58%. This makes September feel drier and warmer, while June provides a cooler yet more humid atmosphere. For more detailed information, you can check Sao Paulo weather in June.
September and July present distinct contrasts in weather conditions. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 35°C (95°F), with an average of 20°C (69°F), while July has cooler temperatures that stretch from 2°C (36°F) to a maximum of 29°C (85°F), averaging just 17°C (62°F). Additionally, September experiences more rainfall, with 40 mm (1.6 in) over about 6 days, compared to July's 25 mm (1.0 in) spread across only 2 days. Humidity levels are also different, with September at 58% and July higher at 72%. For a detailed look at July's climate patterns, you can refer to Sao Paulo weather in July.
In comparing the weather between September and August, September tends to be warmer, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 35°C (95°F), while August has slightly cooler temperatures, with a minimum of 6°C (42°F) and a maximum of 32°C (89°F). The average temperature in September is notably higher at 20°C (69°F) compared to August's average of 17°C (63°F). Additionally, September experiences less precipitation, with 40 mm (1.6 in) over 6 days, whereas August has 57 mm (2.2 in) falling over 7 days. Humidity levels are also somewhat lower in September at 58%, compared to August's 65%. For more insights, you can check out Sao Paulo weather in August.
September and October showcase distinct changes in weather patterns. September typically experiences a temperature range from a minimum of 9°C (48°F) to a maximum of 35°C (95°F), with an average temperature of 20°C (69°F). The month sees about 40 mm (1.6 in) of rainfall over six days and maintains a humidity level of 58%. In contrast, October tends to be slightly warmer, with minimum temperatures of 12°C (53°F) and maximums reaching up to 37°C (99°F), averaging 21°C (70°F). However, this month also brings an increase in precipitation, totaling 118 mm (4.6 in) over 16 days, while humidity decreases to 50%. For more details, you can check out Sao Paulo weather in October.
In September, temperatures range from a cool 9°C (48°F) at night to a warm 35°C (95°F) during the day, with an average of 20°C (69°F). The month sees relatively low precipitation, with only 40 mm (1.6 in) over 6 days and a humidity level of 58%. By contrast, November experiences slightly milder nighttime temperatures at a minimum of 11°C (53°F), while daytime highs can still reach up to 35°C (96°F), maintaining an average of 21°C (69°F). However, November is significantly wetter, recording 116 mm (4.6 in) of rainfall across 15 days, and the humidity rises to 75%. For more details, visit Sao Paulo weather in November.
September and December showcase notable differences in weather patterns. In September, temperatures range from a low of 9°C (48°F) to a comfortable average of 20°C (69°F), peaking at 35°C (95°F). The city experiences moderate precipitation of 40 mm (1.6 in) across about 6 days, with relative humidity at 58%. In contrast, December sees slightly warmer temperatures, with a minimum of 12°C (54°F) and an average of 22°C (72°F), reaching up to 34°C (93°F). However, it is significantly wetter, with precipitation measuring 143 mm (5.6 in) over 21 days and higher humidity at 80%. For a detailed look at the weather conditions in December, you can visit Sao Paulo weather in December.
As September arrives in São Paulo, the city begins to transition into spring, offering a delightful blend of warm days and cooler nights. Temperatures can soar to a maximum of 35°C (95°F), contrasting with the refreshing average of 20°C (69°F), while the crisp minimum temperatures drop to 9°C (48°F). This month typically experiences less rainfall, with an average of 40 mm (1.6 in) spread across about 6 days, making it drier compared to the wetter winter months. With humidity at around 58%, the climate is pleasantly temperate, inviting both locals and tourists to explore the vibrant atmosphere of São Paulo. For a deeper dive into the city's weather patterns, check out Sao Paulo Climate.