Last updated: August 21, 2025
September in Foz do Iguaçu, Brazil, presents a unique blend of warmth and refreshing breezes, with maximum temperatures reaching up to 39°C (102°F) and averaging around 23°C (74°F). While the days can be quite hot, the mercury can dip to a cool 9°C (49°F) at night, creating a delightful contrast. This month also sees an average precipitation of 78 mm (3.1 in) across 6 rainy days, contributing to the lush greenery that the region is renowned for. With a humidity level of 52%, visitors can expect a comfortable atmosphere ideal for exploring the stunning natural beauty of this vibrant locale.
As September rolls into Foz do Iguaçu, the temperatures begin their ascent, setting a warm and inviting tone for the early spring. With minimums around 9°C (49°F) and averages peaking at 23°C (74°F), the city transitions away from the cooler winter months. Notably, highs can soar up to a sweltering 39°C (102°F), reminiscent of the hot summer days that follow. The increase in temperature signals the vibrant blossoming of the region, offering travelers the perfect opportunity to explore the stunning waterfalls and lush landscapes in pleasantly warm conditions. As the month progresses, the combination of milder evenings and sunny days creates an ideal backdrop for outdoor activities in this breathtaking Brazilian destination.
In September, Foz do Iguaçu experiences a modest jump in rainfall, with precipitation reaching 78 mm (3.1 in) over approximately six days. This increase follows the relatively drier months of July and August, which recorded significantly lower amounts at 43 mm (1.7 in) and 76 mm (3.0 in), respectively. As the region transitions into spring, the weather begins to shift, hinting at the wetter months ahead. With precipitation amounts typically rising in October to 171 mm (6.7 in), September acts as a subtle prelude, bridging the gap between the milder winter and the lush, vibrant conditions that characterize the upcoming months.
In September, Foz do Iguaçu experiences a notable uptick in humidity, reaching 52%. This marks a slight increase from the previous months, where August recorded a low 49%, suggesting a gradual rise in moisture as the region transitions from winter to spring. As the year progresses, humidity in Foz do Iguaçu typically fluctuates with the changing seasons; it peaks dramatically in the summer months of January and December, illustrating the Amazonian climate's characteristic dampness. As temperatures rise in the coming months, one can expect humidity to climb further, setting the stage for the lush, vibrant environment Foz do Iguaçu is renowned for.
In September, Foz do Iguacu experiences a UV Index of 10, categorized as very high, with a burn time of just 15 minutes. This indicates a notable resilience in UV radiation as the season transitions, aligning with the broader trend observed in the region. Following the peak of summer months, where the index surges to extreme levels, September's reading reflects a slight dip but still demands vigilance. As the region moves towards the sunnier months of October and November, where the index once again escalates, it’s crucial to stay protected. For continuous updates on UV exposure and safety tips, visit Foz do Iguacu UV Index.
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September in Foz do Iguaçu offers a delightful balance of sunshine, with 278 hours of glorious sunlight gracing the month. This marks a slight dip from the vibrant summer months of January through March, where the sunshine soars above 300 hours. As the days subtly transition into the warmer embrace of spring, September stands out as a cozy precursor to October, which maintains a similar total of 276 hours. Notably, this month is part of a broader trend, where the region experiences an impressive rise in daylight hours as the year progresses, culminating in November's peak of 319 hours. So, bask in the September glow; it's a charming blend of summer's warmth and the anticipation of longer days to come.
In September, Foz do Iguaçu boasts a 59% chance of sunny weather, marking a pleasant transition into spring. This uptick follows a solid summer performance, especially the sun-drenched months of February and July, which reach highs of 67%. While September's likelihood of sunshine is temporarily eclipsed by more favorable conditions in the preceding months, it remains an inviting choice for travelers seeking to enjoy the region's stunning landscapes. As the year progresses towards the summer peak in December—with a remarkable 75% likelihood of sunny evenings—September serves as a charming precursor, hinting at the warm days to come without overwhelming humidity.
As September arrives in Foz do Iguaçu, daylight begins to stabilize after the fluctuations of the preceding months. Following the gradual decline from a generous 13 hours in January down to 10 hours from May through July, September marks a subtle return to longer days, featuring 11 hours of daylight. This trend indicates a shift towards brighter days ahead, as the region transitions through the spring months. As October approaches, daylight duration will continue to increase, offering a warm and inviting atmosphere synonymous with Brazil's vibrant environment.
In September, the winds in Foz do Iguaçu begin to pick up, with an average speed of 2.9 m/s (6 mph), marking a gradual increase from the preceding months. This upward trend is particularly notable as it follows consistently mild winds, such as 2.8 m/s (6 mph) in August and 2.6 m/s (6 mph) in July. As spring approaches in the Southern Hemisphere, the breezy September air not only invigorates the landscape but also invites visitors to explore the stunning sights of the region. Come October, the winds settle back to 2.6 m/s (6 mph), but September’s refreshing gusts serve as a gentle reminder of nature's rhythms.
Weather in Foz do Iguacu varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Foz do Iguacu, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present notable differences in weather patterns. In September, temperatures range from a cooler minimum of 9°C (49°F) to a warm average of 23°C (74°F), with occasional peaks reaching as high as 39°C (102°F). The month experiences a moderate level of precipitation at 78 mm (3.1 in) over approximately 6 days, accompanied by a relative humidity of 52%.
In contrast, January is warmer and more humid, with minimum temperatures starting at 16°C (62°F) and an average of 27°C (80°F), while still allowing for maximum temperatures to reach 39°C (102°F). This month sees significantly higher precipitation totaling 154 mm (6.1 in) across 16 days and a much higher humidity level at 82%. For more detailed information, you can check the Foz do Iguacu weather in January.
September weather is characterized by a broader temperature range, with minimums dropping to 9°C (49°F) and maximums reaching as high as 39°C (102°F). In contrast, February offers milder nights with minimums around 15°C (59°F) and slightly higher average temperatures of 26°C (79°F), although maximums still reach up to 37°C (98°F). When it comes to precipitation, September sees about 78 mm (3.1 in) over 6 days, while February is wetter, with 111 mm (4.4 in) spread across 11 days. Additionally, February experiences higher humidity levels at 79%, compared to September's 52%. For more details, check out Foz do Iguacu weather in February.
In comparing the weather between September and March, one can observe notable differences in temperature and precipitation patterns. September experiences a wider temperature range, with a minimum of 9°C (49°F) and a maximum of 39°C (102°F), averaging around 23°C (74°F). In contrast, March features warmer temperatures, with a minimum of 13°C (55°F), an average of 25°C (78°F), and a maximum of 36°C (97°F). Furthermore, March sees increased rainfall, totaling 121 mm (4.8 in) over 11 days, compared to September's 78 mm (3.1 in) over just 6 days. The humidity also rises significantly in March to 75%, compared to September's more moderate 52%. For more detailed weather insights, you can check out Foz do Iguacu weather in March.
When comparing the weather in September and April, September tends to be warmer, with average temperatures reaching up to 23°C (74°F) and a maximum of 39°C (102°F), while April has a slightly cooler average of 22°C (73°F) with a maximum of 35°C (95°F). In terms of precipitation, April is wetter, receiving 105 mm (4.1 in) of rain, compared to September's 78 mm (3.1 in), both having precipitation on approximately 6 days. Moreover, April exhibits higher humidity levels at 74%, compared to September’s 52%. For more detailed information, you can check Foz do Iguacu weather in April.
In comparing the weather between September and May, we observe distinct differences in temperature and precipitation patterns. September boasts a warmer average temperature of 23°C (74°F), with highs reaching up to 39°C (102°F), while May's average is cooler at 19°C (67°F) with a maximum of 33°C (91°F). Precipitation is notably higher in May, with 149 mm (5.9 in) over approximately 10 days, compared to September's 78 mm (3.1 in) across 6 days. Additionally, humidity levels are more pronounced in May at 75%, contrasted with September's 52%. For more detailed information, you can check Foz do Iguacu weather in May.
In comparing the weather between September and June, we see notable differences. September features a wider temperature range, with minimums around 9°C (49°F), averages at 23°C (74°F), and highs reaching up to 39°C (102°F). In contrast, June experiences cooler conditions, starting at a minimum of 2°C (36°F) with an average of 18°C (64°F) and maximums of 30°C (87°F). Additionally, September has a lower precipitation level at 78 mm (3.1 in) over 6 days, while June sees more rain with 146 mm (5.7 in) over 9 days. Humidity levels are also higher in June at 70%, compared to 52% in September. For more details, you can check the Foz do Iguacu weather in June.
When comparing the weather in September and July, September typically offers warmer temperatures, with a minimum of 9°C (49°F) and an average of 23°C (74°F), while July sees much cooler conditions, with a minimum of 1°C (34°F) and an average of 17°C (63°F). The maximum temperatures in September can reach up to 39°C (102°F), significantly higher than July's peak of 30°C (87°F). Additionally, September experiences more precipitation at 78 mm (3.1 in) over 6 days, compared to July's 43 mm (1.7 in) on the same number of days. However, July has a higher humidity level at 61%, compared to September's 52%. For more detailed information about the weather in July, you can visit Foz do Iguacu weather in July.
In comparing the weather between September and August, September shows a marked increase in both temperature and humidity. September experiences a minimum temperature of 9°C (49°F) and an average high of 39°C (102°F), significantly warmer than August's minimum of 3°C (38°F) and maximum of 34°C (94°F). Precipitation levels are quite similar, with September recording 78 mm over 6 days and August slightly less at 76 mm, also over 6 days. The humidity rises in September to 52%, compared to August's 49%, contributing to a warmer and somewhat more uncomfortable atmosphere. For a closer look at August's weather, you can check Foz do Iguacu weather in August.
In September, the weather features a minimum temperature of 9°C (49°F) and an average of 23°C (74°F), with a maximum reaching up to 39°C (102°F). The month experiences approximately 78 mm (3.1 in) of precipitation over 6 days, with humidity levels around 52%. In contrast, October sees a slight increase in temperatures, with a minimum of 12°C (53°F) and an average of 24°C (75°F), peaking at 40°C (103°F). However, it also brings significantly more rainfall, totaling 171 mm (6.7 in) over 12 days, and slightly higher humidity at 55%. For more detailed information on the weather, check out Foz do Iguacu weather in October.
In September, the weather is characterized by a wide temperature range, with minimums of 9°C (49°F) and maximums soaring up to 39°C (102°F). The average temperature hovers around 23°C (74°F), accompanied by relatively low humidity at 52%. However, September experiences some rainfall, with about 78 mm (3.1 in) of precipitation spread over 6 days.
In contrast, November brings milder minimum temperatures of 14°C (58°F) and averages a comfortable 25°C (77°F), though maximums reach up to 37°C (98°F). This month sees an increase in precipitation, totaling 118 mm (4.7 in) over 9 days, and a notable rise in humidity at 73%. Overall, November feels warmer and more humid compared to September, making it an ideal time for those who enjoy tropical weather. For more detailed insights, check out Foz do Iguacu weather in November.
In September, the weather features a minimum temperature of 9°C (49°F) and an average of 23°C (74°F), peaking at a maximum of 39°C (102°F). The month experiences relatively low precipitation, with about 78 mm (3.1 in) spread over 6 days and moderate humidity at 52%. In contrast, December sees warmer temperatures, starting at a minimum of 14°C (58°F) and averaging 26°C (79°F), with highs reaching 38°C (100°F). However, this month also brings significantly increased rainfall of 155 mm (6.1 in) over 11 days and higher humidity levels at 85%. For a detailed look at December's climate, you can refer to Foz do Iguacu weather in December.
As September unfolds in Foz do Iguacu, the weather begins to transition, marked by a blend of warm days and cooler nights. Unlike the sweltering peak of summer, the average temperature dips to a comfortable 23°C (74°F), offering a pleasant respite for outdoor adventures. While occasional rain graces the region, with about six days of precipitation, the overall humidity remains moderate at 52%, making it a delightful time to explore the breathtaking waterfalls and lush landscapes. For those planning a visit, the unique blend of warmth and the onset of the dry season offers a distinct charm compared to other months. Discover more about the area's climate before you go by visiting Foz do Iguacu Climate.