In terms of precipitation, rainfall in Porto Alegre ranges from 2.8 - 5.1 inches per month. September is typically the wettest month, when rainfall can reach 5.1 in. November is typically the driest time to visit Porto Alegre when rainfall is around 2.8 in.
If weather is an important factor for your trip to Porto Alegre, use this chart to help with planning. For those seeking warmer temperatures, February is the ideal time of year to visit, when temperatures reach an average of 77.0 F. Travelers looking to avoid the cold should look outside of June, when temperatures are typically at their lowest (around 55.4 F).