Last updated: August 21, 2025
In September, São Francisco do Sul, Brazil experiences a delightful transition into spring. With maximum temperatures reaching 31°C (87°F) and an average of 20°C (68°F), the weather is pleasantly warm. However, the evenings can be cool, dipping to a minimum of 9°C (49°F). September is also characterized by notable rainfall, totaling 106 mm (4.2 in) over approximately 14 days, maintaining the region's lush greenery. This month sees high humidity levels averaging 82%, contributing to a tropical feel that is both refreshing and vibrant. Visitors and residents alike can enjoy the charm of this coastal town as it awakens from winter slumber.
In September, Sao Francisco do Sul begins to transition from the chill of winter to the warmth of spring, with temperatures showcasing this shift beautifully. The month starts with a minimum temperature of 9°C (49°F), a noticeable rise from the previous month's lows, and settles into a comfortable average of 20°C (68°F). Daytime highs reach around 31°C (87°F), maintaining the balmy feel characteristic of late winter and early spring. This gradual warming trend hints at the warmer months ahead, allowing residents and visitors alike to enjoy outdoor pursuits in increasingly pleasant weather. Overall, September encapsulates a delightful seasonal change, marked by mild temperatures that beckon for exploration and relaxation along the stunning coast.
In September, Sao Francisco do Sul receives an average precipitation of 106 mm (4.2 in) over approximately 14 days, marking a notable uptick in rainfall as the coastal city transitions into the spring season. This month's totals reflect a slight increase compared to the drier months of July and August, which recorded only 33 mm and 70 mm, respectively. The rainfall in September aligns with the trend of rising precipitation levels leading into the spring months, as it follows a pattern of increasing moisture that peaks in October with 166 mm (6.5 in). While the number of rainy days slightly increases, the overall precipitation amount demonstrates a return to wetter conditions after the relatively dry winter months, setting the stage for the lush landscapes characteristic of the region.
In September, Sao Francisco do Sul experiences a modest dip in humidity at 82%, marking a subtle shift from the higher levels observed during the earlier months of the year. The trend suggests a gradual decline in humidity from the peak of 88% in December through to a low in August, after which the humidity begins to stabilize. This pattern reflects the transitioning seasons, with spring on the horizon as the region prepares to enjoy slightly drier conditions in the coming months. Despite the decrease, September's humidity still remains substantial, providing a lush environment typical of this vibrant coastal area.
As the seasons shift in Sao Francisco do Sul, September marks a notable transition in the UV Index, which stands at 10 this month, categorizing it as very high with a burn time of 15 minutes. Following the summer peak in January and February, where extreme UV levels soared above 14, there's a slight moderation in intensity, yet caution remains paramount. The UV Index gradually declines through the winter months, reaching a low of 6 in June and July, before climbing back up in August and September. This trend highlights the importance of staying vigilant during outdoor activities, especially as the days grow longer leading into spring. For more detailed insights, check out the latest updates on the Sao Francisco do Sul UV Index.
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As September rolls in, Sao Francisco do Sul experiences a delightful consistency in sunshine, accumulating 240 hours of sunlight—aligning perfectly with May's brightness and echoing the energy of January. This pattern hints at a gentle transition from the frosty grip of winter, as the days begin to lengthen and warm up, capturing the essence of early spring. Following the more luminous peak of November and December, where sunlight soars to impressive heights of 296 and 318 hours respectively, September serves as a harmonious blend of summer's lingering warmth and the promising aura of fall. This steady rhythm of sunshine adds a charming backdrop to the vibrant atmosphere of the coastal town, inviting both residents and visitors to bask in its golden glow.
In September, Sao Francisco do Sul experiences a modest chance of sunny days, with only 23% likelihood of clear skies. This marks a slight increase from the more overcast months of August and January but falls short of the brighter prospects seen in the peak of winter, particularly July, which boasts a robust 57% chance of sunshine. As the season shifts into spring, the weather begins to stabilize, hinting at the more favorable conditions that await in late spring and summer. While September may not be the sunniest month, it represents a gentle transition, paving the way for the sun-drenched days of October and beyond.
In Sao Francisco do Sul, Brazil, the rhythm of daylight subtly shifts throughout the year, painting a beautiful picture of seasonal change. As we move from January with a generous 13 hours of daylight to the shorter days of May, where it dips to just 10 hours, a gradual decline is evident. However, as September arrives, daylight makes a gentle comeback, stabilizing at 11 hours, in line with the previous month. This resurgence paves the way for longer days ahead, culminating in a return to 13 hours by November and December. The transition from summer’s brightness to winter’s brevity and back again reflects the region's vibrant seasonal dynamics and offers a captivating glimpse into nature’s cycles.
In São Francisco do Sul, September heralds a subtle yet invigorating shift in the winds. As summer's grip begins to ease, the average wind speed rises to 2.1 m/s (5 mph), marking the beginning of a gentle increase that continues through the subsequent months. This uptick not only contrasts with the calmer summer months of July and August, where winds hovered around 1.7 m/s but also sets the stage for an energetic autumn. With October and November maintaining this pleasant momentum at 2.2 m/s, September serves as a delightful prelude, inviting both locals and visitors to embrace the breezy charm that characterizes this coastal gem. The winds whisper tales of seasonal change, crafting an ideal backdrop for outdoor adventures and tranquil moments alike.
Weather in Sao Francisco do Sul varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Sao Francisco do Sul, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present contrasting weather conditions. In September, temperatures range from a minimum of 9°C (49°F) to a maximum of 31°C (87°F), with an average of 20°C (68°F). This month sees considerable rainfall of 106 mm (4.2 in) over 14 days, and the humidity hovers around 82%. Conversely, January experiences warmer weather, with minimum temperatures of 18°C (64°F) and maximums reaching up to 38°C (101°F), averaging 26°C (78°F). Precipitation in January is significantly higher at 264 mm (10.4 in) over 21 days, alongside slightly increased humidity at 86%. For more detailed insights, check out Sao Francisco do Sul weather in January.
In September, the weather features a mild temperature range with a minimum of 9°C (49°F) and a maximum of 31°C (87°F), averaging around 20°C (68°F). The month receives about 106 mm (4.2 in) of precipitation over 14 days, with humidity at a comfortable 82%. In contrast, February experiences warmer conditions, with minimum temperatures at 16°C (60°F) and maximums soaring to 36°C (98°F), averaging 25°C (77°F). However, it also sees increased rainfall, totaling 204 mm (8.0 in) over 21 days, with humidity slightly higher at 83%. For a more detailed look at February's weather, visit Sao Francisco do Sul weather in February.
September and March present contrasting weather patterns in Sao Francisco do Sul. In September, temperatures range from a cooler minimum of 9°C (49°F) to a warm maximum of 31°C (87°F), with an average of 20°C (68°F). Precipitation is moderate, totaling 106 mm (4.2 in) over 14 days, and humidity hovers around 82%. In contrast, March experiences significantly warmer temperatures, with a minimum of 17°C (63°F) and a maximum reaching 35°C (94°F), resulting in an average of 24°C (76°F). This month also sees a higher rainfall of 199 mm (7.9 in) spread across 25 days, while humidity slightly increases to 85%. For more details on the weather specifics in March, you can visit Sao Francisco do Sul weather in March.
When comparing the weather in September and April, we notice some intriguing similarities and differences. September typically sees minimum temperatures around 9°C (49°F) and average highs of 31°C (87°F), while April starts slightly warmer with minimums of 11°C (52°F) and maximums reaching up to 34°C (93°F). Precipitation levels are relatively close, with September averaging 106 mm (4.2 in) over 14 days and April recording 108 mm (4.3 in) across 15 days. Humidity levels are also quite comparable, with September at 82% and April slightly higher at 85%. For more details on April weather, you can visit Sao Francisco do Sul weather in April.
September and May exhibit quite similar weather patterns, with both months averaging around 20°C (68°F). September presents slightly warmer nights with a minimum of 9°C (49°F) compared to May's cooler minimum of 7°C (45°F). Both months can reach maximum temperatures of 31°C (87°F for September and 88°F for May), offering pleasant warm days. Precipitation levels are comparable, with September receiving 106 mm (4.2 in) across 14 days and May slightly higher at 112 mm (4.4 in) over 15 days, reflecting the transition of seasons. Additionally, humidity is marginally higher in May at 86%, compared to 82% in September. For those interested in May conditions specifically, more details can be found at Sao Francisco do Sul weather in May.
In comparing the weather between September and June, both months feature similar maximum temperatures, peaking at around 31°C (87°F in September and 88°F in June). However, September tends to be warmer overall, with an average temperature of 20°C (68°F), compared to June's average of 18°C (65°F). Precipitation is slightly higher in June, totaling 108 mm over 11 days, compared to September's 106 mm over 14 days. Humidity levels are comparable, with September at 82% and June slightly higher at 85%. For more information on June weather, you can check out Sao Francisco do Sul weather in June.
When comparing the weather in September to July, there are some notable differences. September experiences a wider temperature range, with minimums around 9°C (49°F) and maximums reaching up to 31°C (87°F), compared to July's lower range of 3°C (37°F) to 31°C (88°F). Although both months have similar maximum temperatures, September has a significantly higher average of 20°C (68°F) compared to July's average of 17°C (63°F). Additionally, September sees more precipitation, with 106 mm (4.2 in) falling over 14 days, whereas July has only 33 mm (1.3 in) over just 7 days. Humidity levels are also slightly higher in September at 82%, compared to 80% in July. For more specific details on July’s weather, visit Sao Francisco do Sul weather in July.
In comparing the weather between September and August, September features a notably higher minimum temperature of 9°C (49°F) compared to August's 5°C (41°F), while both months share similar maximum temperatures that peak at around 31°C (87°F) and 31°C (88°F), respectively. The average temperature climbs slightly in September to 20°C (68°F) from August's 18°C (64°F), signifying a shift towards warmer days. Additionally, September witnesses increased precipitation, totaling 106 mm (4.2 in) over 14 days, compared to August's 70 mm (2.7 in) across 10 days, indicating a wetter month. Humidity levels also rise slightly, with September at 82% versus August's 79%. For more detailed insights, you can explore Sao Francisco do Sul weather in August.
In September, the weather is characterized by a mild temperature range, with minimums around 9°C (49°F) and maximums reaching up to 31°C (87°F), averaging 20°C (68°F). Precipitation is common, with 106 mm (4.2 in) falling over 14 days, and the humidity remains high at 82%.
In contrast, October sees a rise in temperatures, with minimums of 12°C (54°F) and maximums soaring to 37°C (99°F), averaging 21°C (70°F). However, October also brings increased rainfall, with a total of 166 mm (6.5 in) over 20 days, maintaining the same humidity level of 82%. For more detailed information, you can view Sao Francisco do Sul weather in October.
September and November showcase distinct weather characteristics. In September, temperatures range from a minimum of 9°C (49°F) to a maximum of 31°C (87°F), with an average temperature of 20°C (68°F). The month experiences around 106 mm (4.2 in) of precipitation over 14 days, accompanied by a humidity level of 82%.
In contrast, November offers warmer temperatures, with a minimum of 13°C (56°F) and a maximum reaching 35°C (95°F), averaging at 22°C (72°F). It also sees increased precipitation, totaling 145 mm (5.7 in) over 21 days, while humidity rises slightly to 86%. For more detailed information, visit Sao Francisco do Sul weather in November.
In September, the weather is mild with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 31°C (87°F), averaging around 20°C (68°F). The month experiences significant rainfall, totaling 106 mm (4.2 in) over approximately 14 days, accompanied by high humidity levels at 82%.
By December, temperatures rise significantly, with a minimum of 15°C (59°F) and a maximum of 36°C (96°F), averaging 24°C (75°F). However, this month sees increased precipitation as well, with 209 mm (8.2 in) of rainfall spread over 21 days and humidity climbing to 88%. For more details, check out Sao Francisco do Sul weather in December.
As September unfolds in Sao Francisco do Sul, the weather begins to transition, showcasing a mix of summer warmth and autumn coolness. Daily temperatures vary widely, with warm days reaching up to 31°C, while nights can dip to a refreshing 9°C. Unlike the dryer months, September sees increased rainfall, totaling around 106 mm spread over 14 days, bringing a vibrant lushness to the region. The humidity remains high at 82%, creating a distinct atmosphere that sets this month apart from the more stable weather patterns of summer and winter. For a deeper dive into what each month has in store, visit Sao Francisco do Sul Climate.