September weather forecast
Brazil

September in Brazil signifies the transition from winter to spring, leading to noticeable shifts in weather patterns across the country. Temperatures in the northeastern regions and the Amazon Basin continue their upward trend, frequently crossing 30°C (86°F) during the day. As the month progresses, the nights become milder, signaling the retreat of winter.

Coastal cities such as Rio de Janeiro start experiencing a mild increase in temperatures, with averages ranging from 22.8°C (73°F) to 27.2°C (81°F). The sea temperatures along the north-central coast rise further, setting the stage for an extended period of pleasant water activities.

In the southern part of Brazil, the harshness of winter starts to subside. Regions south of the Tropic of Capricorn witness a rise in temperatures, marking the end of the frost and snowfall period prevalent in the highlands and mountains. Compared to August, September experiences noticeably warmer temperatures, particularly towards the end of the month.

The precipitation pattern in September marks the onset of the wet season. Rainfall in the Amazon region continues at a steady pace, albeit still lower than the peak wet season. The northeastern regions begin to receive rainfall, marking the end of the dry spell. As the month concludes, rainfall gradually increases across Brazil, signifying the approaching wet season and the full bloom of spring.

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• São Paulo - September »
  In São Paulo, during September, the rain falls for 7 days and regularly aggregates up to 71mm (2.8") of precipitation. In September, in São Paulo, the rain falls for 7 days.
• Rio de Janeiro - September »
  The month with the coldest seawater in Rio de Janeiro, Brazil, is September, with an average sea temperature of 21.6°C (70.9°F). With an average sea temperature of 21.6°C (70.9°F), September is the month with the coldest seawater in Rio de Janeiro.
• Brasília - September »
  In Brasília in September, during 7.8 rainfall days, 19mm (0.75") of precipitation is typically accumulated. September, recording an average high temperature of 30.4°C (86.7°F) and a low temperature of 18.4°C (65.1°F), is Brasília's warmest month.
• Salvador - September »
  Salvador transitions into September recording an average high-temperature of a still moderately hot 27.2°C (81°F), closely aligning with the preceding month's temperature. In Salvador in September, the average water temperature is 25.8°C (78.4°F).
• Fortaleza - September »
  In September, the average heat index, which factors the actual air temperature with the relative humidity, is calculated to be 37°C (98.6°F). During September, Fortaleza's temperature falls to a steady low-temperature average of 23.4°C (74.1°F).
• Belo Horizonte - September »
  In Belo Horizonte, Brazil, during September, the rain falls for 6 days and regularly aggregates up to 41mm (1.61") of precipitation. On the last day of September, in Belo Horizonte, sunrise is at 05:37 and sunset at 17:53 -03.
• Manaus - September »
  The months with the lowest humidity in Manaus are August and September, with an average relative humidity of 77%. With its average high temperature of 32.9°C (91.2°F) and a low of 23.5°C (74.3°F), September is regarded as the warmest month in Manaus, Brazil.
• Curitiba - September »
  In Curitiba in September, during 9 rainfall days, 119mm (4.69") of precipitation is typically accumulated. In Curitiba, Brazil, in September, during 9 rainfall days, 119mm (4.69") of precipitation is typically accumulated.
• Recife - September »
  August and September, with an average sea temperature of 26.4°C (79.5°F), are months with the coldest seawater in Recife, Brazil. In Recife in September, it is raining for 13 days, with typically 122mm (4.8") of accumulated precipitation.
• Porto Alegre - September »
  In Porto Alegre during September, the rain falls for 13.9 days and regularly aggregates up to 66mm (2.6") of precipitation. In Porto Alegre in September, it is raining for 13.9 days, with typically 66mm (2.6") of accumulated precipitation.
• Goiânia - September »
  September tends to be the warmest month in Goiânia with temperatures averaging a daily high of 31.9°C (89.4°F) and a low of 18.1°C (64.6°F). On the first day of September in Goiânia sunrise is at 06:23 and sunset at 18:10.
• Guarulhos - September »
  On the first day of September in Guarulhos sunrise is at 06:16 and sunset at 17:55. As Guarulhos welcomes September, the average high-temperature stabilizes at a moderately hot 23°C (73.4°F), showing little deviation from August's 22°C (71.6°F).