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 in September, during 7 rainfall days, 71mm (2.8") of precipitation is typically accumulated. In São Paulo, Brazil, during September, the rain falls for 7 days and regularly aggregates up to 71mm (2.8") of precipitation.
• Rio de Janeiro - September »
  September is the month with the coldest seawater in Rio de Janeiro, with an average sea temperature of 21.6°C (70.9°F). September is the month with the coldest seawater in Rio de Janeiro, with an average sea temperature of 21.6°C (70.9°F).
• Brasília - September »
  In Brasília in September, during 7.8 rainfall days, 19mm (0.75") of precipitation is typically accumulated. In September, rainfall figures rise to 19mm (0.75") in Brasília heralding the beginning of a wetter season.
• Salvador - September »
  On the first day of September in Salvador sunrise is at 05:37 and sunset at 17:29. The months with the highest UV index in Salvador are January through March, September through December, with an average maximum UV index of 12.
• Fortaleza - September »
  September is the month with the coldest seawater in Fortaleza with an average sea temperature of 26.6°C (79.9°F). In Fortaleza in September, the average water temperature is 26.6°C (79.9°F).
• Belo Horizonte - September »
  On the first day of September in Belo Horizonte sunrise is at 06:03 and sunset at 17:47. On the first day of September in Belo Horizonte sunrise is at 06:03 and sunset at 17:47.
• Manaus - September »
  The months with the lowest humidity in Manaus are August and September, with an average relative humidity of 77%. The months with the lowest humidity in Manaus are August and September, with an average relative humidity of 77%.
• Curitiba - September »
  In Curitiba, during September, the rain falls for 9 days and regularly aggregates up to 119mm (4.69") of precipitation. With the commencement of Spring in Curitiba September witnesses a gradual boost in temperatures and a surge in precipitation.
• 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. August and September, with an average sea temperature of 26.4°C (79.5°F), are months with the coldest seawater in Recife.
• Porto Alegre - September »
  On the first day of September in Porto Alegre, sunrise is at 06:39 and sunset at 18:10. On the last day of September, in Porto Alegre, sunrise is at 06:03 and sunset at 18:25 -03.
• Goiânia - September »
  On the first day of September in Goiânia sunrise is at 06:22 and sunset at 18:10. In Goiânia, the month of September registers the highest temperatures, averaging 31.9°C (89.4°F) at the peak and 18.1°C (64.6°F) at the lowest.
• Guarulhos - September »
  On the first day of September in Guarulhos, sunrise is at 06:16 and sunset at 17:55. In September, in Guarulhos, Brazil, the rain falls for 9 days.