Click on a day for an hourly weather forecast
The temperatures in Porto Alegre in September are comfortable with low of 13°C and and high up to 23°C.
You can expect rain for roughly half of the month of September in Porto Alegre. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Porto Alegre in September 2025.
If you’re planning to visit Porto Alegre in the near future, we highly recommend that you review the 14 day weather forecast for Porto Alegre before you arrive.
Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
---|---|---|---|---|---|---|---|
January | 31° / 20° | 8 | 23 | 0 | 161 mm | Ok | Porto Alegre in January |
February | 31° / 20° | 8 | 21 | 0 | 155 mm | Ok | Porto Alegre in February |
March | 28° / 18° | 7 | 24 | 0 | 130 mm | Good | Porto Alegre in March |
April | 26° / 16° | 6 | 25 | 0 | 108 mm | Perfect | Porto Alegre in April |
May | 22° / 13° | 6 | 25 | 0 | 155 mm | Good | Porto Alegre in May |
June | 19° / 11° | 6 | 24 | 0 | 169 mm | Good | Porto Alegre in June |
July | 19° / 11° | 7 | 24 | 0 | 204 mm | Ok | Porto Alegre in July |
August | 22° / 12° | 6 | 25 | 0 | 182 mm | Good | Porto Alegre in August |
September | 23° / 13° | 8 | 22 | 0 | 187 mm | Good | Porto Alegre in September |
October | 25° / 15° | 8 | 23 | 0 | 194 mm | Good | Porto Alegre in October |
November | 27° / 17° | 6 | 24 | 0 | 141 mm | Perfect | Porto Alegre in November |
December | 30° / 19° | 7 | 24 | 0 | 134 mm | Ok | Porto Alegre in December |