September Weather in Barreirinhas, Brazil

Last updated: August 21, 2025

In September, Barreirinhas, Brazil basks in warm and inviting weather, with maximum temperatures soaring up to 35°C (95°F) and an average of 28°C (83°F), providing ideal conditions for outdoor adventures. The nights are pleasantly mild, with minimum temperatures around 23°C (74°F). Remarkably, the month witnesses virtually no rainfall, accumulating only 6 mm (0.2 in), ensuring clear skies and ample sunshine for visitors to explore the stunning landscapes of the Lençóis Maranhenses National Park. With humidity levels at a comfortable 51%, September is a prime time to experience the natural beauty and vibrant culture of this enchanting coastal destination.

September Temperature in Barreirinhas

As September rolls into Barreirinhas, Brazil, the temperature begins to reflect a vibrant transition into warmer days. The month boasts a minimum temperature of 23°C (74°F), providing a comfortable foundation for the average of 28°C (83°F) that enlivens the landscape. With maximum temperatures reaching a sweltering 35°C (95°F), September enjoys the peak heat of late Brazilian winter, matching the intensity typically felt in August. This slight uptick in warmth accompanies a gradual shift into spring, inviting both locals and visitors to revel in the sultry sun while exploring the stunning natural beauty of the region. Overall, September is a time where the balmy temperatures set the stage for vibrant outdoor adventures amidst Barreirinhas' breathtaking scenery.

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

The chart illustrates September temperature patterns in Barreirinhas, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Barreirinhas, 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).
JanFebMarAprMayJunJulAugSepOctNovDec818080808181818282828382
Data source: Temperature data for Barreirinhas generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Barreirinhas

In Barreirinhas, Brazil, September marks a notable transition in the precipitation pattern. With a mere 6 mm (0.2 in) of rain recorded throughout the month, it stands out as one of the driest periods in the year, accompanied by no precipitation days. This sharp decline follows the heavy rainfall experienced from January through August, where monthly averages peaked significantly, especially in March with 349 mm (13.7 in). As the region shifts from its wet season, September serves as a clear indicator of the drying trend that continues into October, suggesting a lull before the remnant rains return. This pattern highlights Barreirinhas' unique climate cycle, showcasing how quickly the landscape can transition from lush to arid.

September Precipitation Trends in Barreirinhas

The chart displays monthly precipitation patterns in Barreirinhas, 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 Barreirinhas, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec1353023493282367053116113559
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Barreirinhas

As the months unfold in Barreirinhas, Brazil, a distinct trend in humidity levels emerges, particularly in September when the humidity reaches a comfortable 51%—the lowest since the drier season began in late summer. Following the peak of 92% in April, the region experiences a significant drop, with humidity steadily declining from August's 55%. This gradual decrease signals a transition into the drier months, making September an ideal time to explore the stunning landscapes without the oppressiveness of high humidity. As the year progresses, humidity levels begin to rise again, hinting at the return of the lush, tropical climate typical of Barreirinhas.

September Average Humidity in Barreirinhas

This chart illustrates the average monthly humidity levels in Barreirinhas, 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 Barreirinhas is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%90%90%92%89%79%64%55%51%53%60%78%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Barreirinhas

In September, Barreirinhas, Brazil, continues to embrace its summer-like intensity with a UV Index of 13, categorized as extreme. This reflects a slight dip from the peak values earlier in the year, yet still underscores the need for caution when enjoying the sun. With a consistent burn time of just 10 minutes, beachgoers should remain vigilant and adequately protected against skin damage. As we move into October, the UV Index holds steady at 13, indicating that while the intensity may wane slightly, the potential for harm remains high. For those looking to plan their sun exposure, staying informed is key—check out more details at Barreirinhas UV Index.

Maximum UV Index Levels in Barreirinhas for September

The chart shows the monthly maximum UV Index (UVI) for Barreirinhas 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 Barreirinhas typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec151516151312111313131413
Data source: Barreirinhas 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 Barreirinhas

September in Barreirinhas, Brazil, offers a delightful blend of sunny days, boasting 339 hours of sunshine that perfectly captures the spirit of early spring. As summer wanes, the sunlight begins to soften while still providing ample warmth, making this month particularly appealing for outdoor adventures and exploration. With September following a peak in sunshine during August, which had 347 hours, it marks a slight decline yet remains significantly higher than the earlier months of the year. This trend of increasing sunshine continues as October approaches, promising even 356 hours ahead. Visitors can revel in the vibrant landscapes and charming ambiance that Barreirinhas offers during this radiant month, making the most of the lingering summer vibes.

Monthly Sunshine Duration in Barreirinhas: September Highlighted

The September sunshine duration represents the total number of hours Barreirinhas 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.
JanFebMarAprMayJunJulAugSepOctNovDec246h253h284h269h305h323h343h347h339h356h335h320h
Data source: Barreirinhas September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Barreirinhas During September

In Barreirinhas, Brazil, September offers a promising chance of sunny weather, with a 59% likelihood of sunshine. This vibrant month follows a remarkable upward trend in clear skies, as the sunny days gradually increase from the relatively modest 18% in January to a peak of 66% in August. While September's sunshine probability slightly tapers off compared to August, it remains robust, reflecting a transition into the more favorable conditions of the latter part of the year. As travelers and locals alike anticipate the end of winter, the pleasant weather in September beckons visitors to explore the spectacular dunes and rich landscapes of the region.

Percentage of Sunny Days in September in Barreirinhas

The chart illustrates the percentage of sunny days in Barreirinhas 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 Barreirinhas experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec18%23%14%28%37%52%58%66%59%55%47%30%
Data source: Barreirinhas September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Barreirinhas in September

In Barreirinhas, Brazil, the daylight duration reveals an intriguing pattern throughout the year. From January to April, residents and visitors enjoy a consistent 12 hours of daylight, providing ample time to explore the stunning landscapes. As May rolls in, daylight begins to decrease slightly to 11 hours, a trend that persists through June and July, ushering in the cooler months. However, this dip is short-lived; by August, the daylight extends back to 12 hours, and this generous duration continues into September and beyond, reaffirming Barreirinhas’s appeal for outdoor activities and vibrant sunsets year-round. The balance of light and dark creates an inviting atmosphere that enhances the charm of this coastal gem.

Average Daylight Hours in Barreirinhas for September

The chart illustrates the variation in daylight duration in Barreirinhas throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec12h 14m12h 10m12h 6m12h 1m11h 58m11h 57m11h 57m12h12h 4m12h 9m12h 13m12h 15m
Data source: Barreirinhas daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Barreirinhas

As September rolls into Barreirinhas, Brazil, the winds begin to pick up, reaching an average speed of 5.0 m/s (11 mph). This marks a noticeable increase compared to the lighter breezes of earlier months like May, which saw just 2.5 m/s (6 mph). The trend signifies a transition from the milder winds of winter into a more invigorating atmosphere as spring approaches. With September's gusts being amongst the highest recorded this year, it's a perfect time for adventure seekers to embrace the elements, whether it's for kitesurfing or enjoying a leisurely walk along the stunning dunes, as the winds whisper secrets of the season's change.

Average September Wind Speed in Barreirinhas

The chart displays monthly wind speed patterns in Barreirinhas, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.23.83.03.22.52.93.44.05.0 m/s4.94.44.8
Data source: Barreirinhas September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Barreirinhas Compares to Other Months

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

September and January present distinct weather contrasts. In September, temperatures typically range from a minimum of 23°C (74°F) to a maximum of 35°C (95°F), with an average of 28°C (83°F), while humidity hovers around 51%. This month sees minimal precipitation, totaling only 6 mm (0.2 in) and with no rainy days. In stark contrast, January experiences a cooler average temperature of 27°C (81°F), with highs up to 33°C (91°F) and consistent humidity levels reaching 89%. This month is marked by substantial rainfall, accumulating 135 mm (5.3 in) over 22 rainy days. For more details on January's weather, check out Barreirinhas weather in January.

September and February present starkly contrasting weather conditions. In September, the temperatures are generally warm, with minimums around 23°C (74°F) and average highs reaching 35°C (95°F). The month is characterized by low precipitation, averaging only 6 mm with no rainy days, and humidity levels sitting at a comfortable 51%. In contrast, February sees similar minimum temperatures of 23°C (73°F) but average highs drop to 32°C (91°F). The month is marked by heavy rainfall, with a staggering total of 302 mm (11.9 in) over 27 days, resulting in significantly higher humidity at 90%. This makes February feel much wetter and more humid overall. For a closer look at February weather specifics, visit Barreirinhas weather in February.

In September, Barreirinhas experiences warm temperatures with a minimum of 23°C (74°F) and an average high of 35°C (95°F), while rainfall is virtually nonexistent, with only 6 mm of precipitation over the month. The humidity is relatively comfortable at 51%. In contrast, March brings a significant shift in weather, as the minimum temperature remains similar at 23°C (73°F), but the average high drops to 32°C (91°F). March is characterized by heavy rainfall, accumulating 349 mm (13.7 in) over 30 days, along with increased humidity levels at 90%. This stark contrast highlights September as a drier, sunnier month, while March tends to be much wetter and more humid. For more detailed insights, check out Barreirinhas weather in March.

When comparing the weather in September and April, notable differences emerge. September typically enjoys warmer temperatures, with a minimum of 23°C (74°F) and an average of 28°C (83°F), peaking at 35°C (95°F). This month also boasts minimal precipitation, averaging only 6 mm (0.2 in) with 0 rainy days and a humidity level of 51%. In contrast, April features slightly cooler temperatures with a minimum of 22°C (73°F) and an average of 27°C (81°F), reaching a maximum of 32°C (91°F). However, April is characterized by significant rainfall, accumulating 328 mm (12.9 in) over 28 days and a much higher humidity level of 92%. For a deeper look at April’s weather, you can explore Barreirinhas weather in April.

When comparing the weather in September and May, noticeable differences arise in temperature and precipitation. September boasts warmer temperatures, with a minimum of 23°C (74°F), an average of 28°C (83°F), and a peak of 35°C (95°F). In contrast, May features slightly cooler conditions, with temperatures ranging from a minimum of 22°C (73°F) to a maximum of 32°C (91°F). However, May is significantly wetter, receiving 236 mm (9.3 in) of rainfall over 22 days, compared to September's dry and humid conditions with just 6 mm (0.2 in) of precipitation and no rainy days. The humidity is also markedly higher in May at 89%, versus 51% in September. For a closer look at May's weather, visit Barreirinhas weather in May.

In comparing the weather between September and June, we notice distinct differences that characterize each month. September tends to be warmer, with average temperatures reaching 28°C (83°F) and maximums peaking at 35°C (95°F), while June has a slightly cooler average of 27°C (82°F) and a maximum of 32°C (90°F). Additionally, September is notably drier, recording only 6 mm (0.2 in) of precipitation and no rainy days, in stark contrast to June, which experiences significant rainfall at 70 mm (2.8 in) over 12 days, contributing to a higher humidity level of 79%. For more specific details, you can refer to Barreirinhas weather in June.

In comparing the weather of September and July, September boasts slightly higher temperatures, with averages reaching 28°C (83°F) compared to July's 27°C (81°F). Both months see mild minimum temperatures, but September can peak at 35°C (95°F), making it hotter than July's maximum of 33°C (92°F). A notable difference lies in precipitation; September experiences a dry spell with only 6 mm (0.2 in) over 0 days, while July is considerably wetter, receiving 53 mm (2.1 in) across 8 days, contributing to a higher humidity level of 64% compared to September's 51%. For a closer look at July weather specifics, check out Barreirinhas weather in July.

In September, the weather remains warm, with a minimum temperature of 23°C (74°F) and an average of 28°C (83°F), similar to August's average. However, September experiences slightly less humidity at 51%, compared to August's 55%. Notably, September is drier, reporting only 6 mm (0.2 in) of precipitation over 0 days, while August had 11 mm (0.4 in) of rain spread across 2 days. For more detailed insights into the weather during August, visit Barreirinhas weather in August.

In comparing the weather of September and October, both months maintain a similar average temperature of 28°C (83°F), but October sees a slight rise in minimum and maximum temperatures, reaching 24°C (76°F) and 35°C (96°F) respectively. September experiences no precipitation, while October has a total of 11 mm (0.4 in) spread over three days, indicating a more humid environment with increased humidity levels of 53%. For those interested in more details, you can explore the Barreirinhas weather in October.

In comparing the weather between September and November, we see some notable differences. September boasts warmer temperatures, with a minimum of 23°C (74°F) and a maximum of 35°C (95°F), alongside very little rainfall—only 6 mm over zero days—and a humidity level of 51%. In contrast, November experiences slightly cooler temperatures, with a minimum of 24°C (75°F) and a maximum of 34°C (93°F), but it brings significantly more rain, with 35 mm spread over 8 days, resulting in higher humidity at 60%. For more specific details on November weather, check out Barreirinhas weather in November.

In September, Barreirinhas experiences warm temperatures, with a minimum of 23°C (74°F) and an average of 28°C (83°F), reaching up to a maximum of 35°C (95°F). The month is relatively dry, with only 6 mm (0.2 in) of precipitation reported on 0 days and humidity levels at a comfortable 51%. In contrast, December sees similar temperatures, maintaining a minimum of 23°C (74°F) and an average of 28°C (83°F), but with a slightly cooler maximum of 34°C (94°F). However, December is much wetter, experiencing 59 mm (2.3 in) of precipitation over 13 days, resulting in a higher humidity level of 78%. For more details on December weather, visit Barreirinhas weather in December.

Compare Barreirinhas's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Barreirinhas

As September unfolds in Barreirinhas, residents and visitors alike can relish in the warmth and dry conditions that set it apart from other months. With maximum temperatures reaching up to 35°C and an average of 28°C, the weather is pleasantly hot without the interruptions of rain, as the month sees no precipitation days. The humidity remains moderate at 51%, contributing to an overall enjoyable tropical climate. This makes September an ideal time for outdoor adventures and exploring the stunning landscapes of the region. For a deeper dive into what to expect throughout the year, check out Barreirinhas Climate.