September Weather in Itajai, Brazil

Last updated: August 21, 2025

September in Itajai, Brazil offers a delightful transition into spring, showcasing a maximum temperature of 26°C (79°F) and an average of 19°C (66°F), perfect for enjoying outdoor activities. As temperatures dip to a minimum of 10°C (51°F), visitors can expect a refreshing chill in the evenings. This month sees 109 mm (4.3 in) of rainfall spread across approximately 13 days, contributing to the lush and vibrant landscape. With an elevated humidity level of 82%, the air feels pleasantly warm, making September an ideal time to experience the beauty of this coastal gem.

September Temperature in Itajai

In September, Itajai, Brazil, experiences a delightful shift as temperatures begin to warm up, moving away from the cooler winter months. With minimums around 10°C (51°F) and a comfortable average of 19°C (66°F), the city enjoys more pleasant days, while highs reach up to 26°C (79°F). This transitional month signals the approach of spring, making it a perfect time for outdoor activities as the warmth gradually expands compared to the preceding chilly August. As the month progresses, one can expect a gentle increase in day length and warmth, encouraging both locals and visitors to embrace the vibrant atmosphere of the coastal town.

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

The chart illustrates September temperature patterns in Itajai, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Itajai, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec767574716663616266687073
Data source: Temperature data for Itajai generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Itajai

In September, Itajaí experiences a moderate shift in precipitation, recording 109 mm (4.3 inches) of rain over 13 days. This marks a significant increase from the drier months of July and August, which saw only 49 mm (1.9 inches) and 71 mm (2.8 inches), respectively. As the month progresses, it signals the transition into the wetter season, foreshadowing the heavier rains that follow in October with 149 mm (5.9 inches). Notably, September's precipitation is a stark contrast to the lighter downpours at the beginning of the year, emphasizing a gradual escalation in rainfall as the region prepares for the warmer months ahead. This trend highlights how September serves as a bridge between the dry winter and the upcoming burst of summer rains, shaping the landscape and agricultural activities in the area.

September Precipitation Trends in Itajai

The chart displays monthly precipitation patterns in Itajai, 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 Itajai, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec197175156941211285071109149123175
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Itajai

In September, Itajai experiences a mild dip in humidity at 82%, marking a transition as the city edges closer to the warmer months. This slight decrease mirrors the trend seen from August's 79%, suggesting a gradual cooling off before the peak summer months. Overall, the humidity levels in Itajai are fairly consistent throughout the year, fluctuating between 79% in August and a peak of 88% in December. The months leading up to September, like June and July, demonstrate a notable tendency for lower humidity, while the late spring and summer months consistently push the humidity back up, illustrating the region's tropical climate. This rhythmic dance of humidity levels contributes to Itajai's vibrant atmosphere, making it a unique spot year-round.

September Average Humidity in Itajai

This chart illustrates the average monthly humidity levels in Itajai, 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 Itajai is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec86%83%85%85%86%85%80%79%82%82%86%88%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Itajai

In September, Itajai experiences a UV Index of 10, categorizing it as very high and indicating a burn time of just 15 minutes for unprotected skin. This trend is reflective of the region's transition from the intense summer months, peaking in January and February, where UV levels reach a formidable 15 and 14 with an extreme exposure category. As the year progresses into autumn, a slight dip in UV intensity occurs, dropping to a moderate 5 in June and July before spiking again in September. This pattern highlights the importance of sun protection as summer approaches, as the UV Index will soon climb back to extreme levels in the following months. For comprehensive information on UV exposure in Itajai, visit Itajai UV Index.

Maximum UV Index Levels in Itajai for September

The chart shows the monthly maximum UV Index (UVI) for Itajai 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 Itajai typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec15141210755810121415
Data source: Itajai 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.

September Sunshine in Itajai

In September, Itajai enjoys a warm embrace of sunshine with 241 hours of glorious daylight, perfectly transitioning from the vibrant winter months. While this marks a slight dip from the sun-drenched heights of February and March, it still reflects a comfortable continuation of warmth as the city prepares for spring. Following the cooler, cloudier days of June and July, the gradual increase in sunshine hours peeks again in the later months, highlighting November and December as the stars of the year, basking in 298 and 323 hours respectively. As September unfurls its sunny days, Itajai hints at brighter times ahead, making it a delightful period for enjoying the outdoors before the peak of summer.

Monthly Sunshine Duration in Itajai: September Highlighted

The September sunshine duration represents the total number of hours Itajai experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec242h292h299h279h246h220h263h247h241h248h298h323h
Data source: Itajai September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Itajai During September

In September, Itajai experiences a 24% chance of sunny weather, which marks a decline compared to the sunnier months of July and August, where the probabilities reach 55% and 29%, respectively. This dip in sunshine presages the approach of spring, as it also follows the generally brighter periods of late winter. Notably, while the chances remain lower than many months, they stand above the less favorable conditions seen in October. This trend reflects a gradual transition in the weather, hinting at the potential for more vibrant days ahead as the season progresses.

Percentage of Sunny Days in September in Itajai

The chart illustrates the percentage of sunny days in Itajai throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Itajai experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec17%49%30%47%48%34%55%29%24%14%27%36%
Data source: Itajai September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Itajai in September

In Itajai, Brazil, the rhythm of daylight unfolds beautifully throughout the year. September marks a transition, with 11 hours of daylight inviting a gradual return to longer days after the winter months. Following a consistent 10 hours in both June and July, daylight begins to lengthen again, setting the stage for the vibrant spring season to come. As October approaches, sunlight increases to 12 hours, paving the way for the longer days of November and December, each boasting 13 hours of radiant daylight. This ebb and flow not only beckons residents to enjoy the outdoors but also reflects the charming cyclical nature of life in this coastal city.

Average Daylight Hours in Itajai for September

The chart illustrates the variation in daylight duration in Itajai throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec13h 36m12h 59m12h 12m11h 24m10h 45m10h 27m10h 37m11h 11m11h 56m12h 44m13h 26m13h 47m
Data source: Itajai daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Itajai

As September arrives in Itajai, Brazil, the winds gently shift, averaging 2.8 m/s (6 mph)—a slight uptick from the more tranquil summer months. Following the summer's calm, characterized by January's 3.1 m/s and February's 2.7 m/s, September signals a subtle transition towards breezier conditions, paving the way for October’s invigorating increase to 3.3 m/s (7 mph). This gradual rise in wind speed reflects a rhythm of change as the seasons advance, hinting at the upcoming vitality of spring and more robust gusts. With pleasant breezes, September offers a perfect balance—a time for outdoor activities under the warm Brazilian sun, all while embracing the refreshing whispers of the approaching winds.

Average September Wind Speed in Itajai

The chart displays monthly wind speed patterns in Itajai, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.12.72.42.92.72.92.52.42.8 m/s3.33.33.3
Data source: Itajai September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Itajai Compares to Other Months

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

In comparing the weather between September and January, there are notable differences in temperature and precipitation levels. September typically experiences milder temperatures, with average highs around 26°C (79°F) and lows dipping to 10°C (51°F), along with substantial humidity at 82%. In contrast, January brings warmer weather, with average highs reaching 34°C (93°F) and lows at 19°C (66°F), accompanied by higher precipitation levels of 197 mm (7.7 in) over 20 days, compared to September’s 109 mm (4.3 in) over 13 days. Overall, January is characterized by warmer temperatures and more frequent rainfall. For more detailed insights, you can check Itajai weather in January.

In September, the weather features milder temperatures, with a minimum of 10°C (51°F) and a comfortable average of 19°C (66°F), peaking at 26°C (79°F). The month sees 109 mm (4.3 in) of rainfall spread over 13 days, accompanied by a humidity level of 82%. In contrast, February offers warmer conditions, with minimum temperatures rising to 16°C (61°F), an average of 24°C (76°F), and maximums reaching as high as 34°C (93°F). However, it also experiences more precipitation, totaling 175 mm (6.9 in) over 19 days, with humidity slightly higher at 83%. For insights on specific February weather patterns, visit Itajai weather in February.

In comparing the weather of September and March in Itajai, we see distinct differences. September experiences cooler temperatures with a minimum of 10°C (51°F) and an average of 19°C (66°F), while March enjoys warmer conditions, with temperatures ranging from a minimum of 18°C (64°F) to an average of 24°C (75°F). Additionally, March tends to be wetter, with 156 mm (6.1 in) of precipitation over 22 days compared to September's 109 mm (4.3 in) over 13 days. Both months exhibit high humidity levels, but March is slightly more humid at 85% compared to September's 82%. For more details, check out Itajai weather in March.

When comparing the weather in September and April, we observe some notable differences. September typically has slightly cooler temperatures, with a minimum of 10°C (51°F) and a maximum of 26°C (79°F), averaging around 19°C (66°F). In contrast, April features warmer conditions, with minimums of 12°C (55°F) and maximums reaching 29°C (84°F), leading to a higher average of 21°C (71°F).

Additionally, April experiences slightly less precipitation, totaling 94 mm (3.7 in) over about 15 days, compared to September's 109 mm (4.3 in) over 13 days. Both months have high humidity levels, with September at 82% and April slightly higher at 85%. For more details about April weather patterns, you can check Itajai weather in April.

When comparing the weather in September and May, we see some similarities as well as notable differences. In both months, average temperatures are quite close, with September experiencing a minimum of 10°C (51°F) and an average of 19°C (66°F), while May has a slightly lower minimum of 9°C (49°F) and a higher maximum of 29°C (84°F). Precipitation levels also differ, with September receiving 109 mm (4.3 in) over 13 days and May reporting slightly more at 121 mm (4.8 in) over 14 days. Furthermore, May tends to be a bit more humid, with levels reaching 86%, compared to September's 82%. For more detailed insights, you can visit Itajai weather in May.

When comparing the weather of September and June, both months exhibit similar maximum temperatures, peaking at around 26°C (79°F) to 80°F. However, September experiences a slightly higher average temperature of 19°C (66°F) compared to June’s average of 17°C (64°F). In terms of humidity, September is slightly less humid at 82%, relative to June's 85%. Precipitation is more frequent in June, with 128 mm (5.1 in) over 11 days versus September's 109 mm (4.3 in) spread across 13 days. For more detailed insights on June weather, you can visit Itajai weather in June.

In comparing the weather between July and September, there are notable differences in temperature and precipitation. September experiences milder temperatures, with a minimum of 10°C (51°F), an average of 19°C (66°F), and a maximum of 26°C (79°F), while July has cooler minimums at 4°C (40°F) and a lower average of 16°C (61°F). Additionally, September brings significantly more precipitation, accumulating 109 mm (4.3 in) over 13 days, compared to July's 49 mm (1.9 in) over just 7 days. Both months have high humidity levels, with September slightly higher at 82% compared to July's 80%. For more detailed information on July's weather patterns, you can check Itajai weather in July.

In comparing the weather of September and August, September tends to be slightly warmer overall, with an average temperature of 19°C (66°F) compared to August's average of 17°C (62°F). The minimum temperature in September is also higher at 10°C (51°F), while August starts cooler at 6°C (43°F). However, September experiences more rainfall, with 109 mm (4.3 in) of precipitation over 13 days, in contrast to August's 71 mm (2.8 in) across 10 days. Humidity levels are similar, with September at 82% and August at 79%. For more detailed information on August's weather in Itajai, you can visit Itajai weather in August.

In September, temperatures range from a minimum of 10°C (51°F) to a maximum of 26°C (79°F), with an average of 19°C (66°F). The month experiences 109 mm (4.3 in) of precipitation over 13 days, while humidity remains constant at 82%. In contrast, October brings slightly warmer temperatures, with a minimum of 13°C (55°F) and a maximum of 30°C (87°F), resulting in an average of 20°C (68°F). However, October also sees increased precipitation, totaling 149 mm (5.9 in) over 18 days, while humidity stays the same at 82%. For more detailed insights, you can refer to Itajai weather in October.

In September, the weather features a milder range of temperatures, with a minimum of 10°C (51°F) and a maximum of 26°C (79°F), averaging around 19°C (66°F). This month experiences 109 mm (4.3 in) of precipitation over 13 days, accompanied by a humidity level of 82%.

In contrast, November sees an increase in both temperature and humidity. The minimum temperature rises to 13°C (56°F), peaking at 30°C (86°F) for an average of 21°C (70°F). Rainfall also increases to 123 mm (4.8 in) over 19 days, with humidity reaching 86%. For more detailed information, you can check Itajai weather in November.

In comparing the weather between September and December, we can observe notable differences. September typically experiences a milder temperature range with minimums around 10°C (51°F) and maximums reaching up to 26°C (79°F), while December sees higher temperatures, with a minimum of 14°C (58°F) and maximums soaring to 31°C (88°F). Additionally, December has a higher average precipitation of 175 mm (6.9 in), spread over 21 days, compared to September's 109 mm (4.3 in) over 13 days. Humidity also rises slightly from 82% in September to 88% in December, contributing to a more humid atmosphere during the latter month. For a deeper dive into the specifics of December weather, you can refer to Itajai weather in December.

Compare Itajai's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Itajai

As September rolls in, Itajai's weather reveals a notable shift, transitioning from the cooler winter months to the more temperate spring conditions. With an average temperature around 19°C (66°F), the month boasts milder days compared to the chilling lows experienced earlier in the year. However, September also introduces increased rainfall, with 109 mm (4.3 in) recorded over approximately 13 rainy days, making it one of the wetter periods. This slight uptick in humidity, hovering around 82%, ensures that while temperatures are more comfortable, the air feels a bit heavier. For a deeper insight into the climate trends in Itajai, check out Itajai Climate.