Jornal Nacional provided a comprehensive weather forecast for Carnival Sunday in Brazil, announcing a significant heat wave alongside potential storms in several areas. Warnings are in effect from Friday night until Saturday in the southern regions, particularly impacting North Rio Grande do Sul, Santa Catarina, and Paraná. A risk of heavy rainfall is also expected from Piauí to Amapá and from Amazonas to Acre, with cities like Rio Branco, Porto Velho, Macapá, and Belém particularly at risk for substantial rainfall.

In contrast, many areas will experience stable weather with high temperatures. Places like Boa Vista and Rio de Janeiro are forecasted to reach maximum temperatures of 35°C. Other cities such as Vitória, Goiânia, and Cuiabá are expected to see temperatures ranging from 33°C to 34°C. Major urban centers including Salvador, Belo Horizonte, and São Paulo anticipate warm weather around 32°C, while Recife will be slightly cooler at 31°C, and Porto Alegre at 30°C.

As the Carnival celebrations commence, the weather conditions are particularly relevant for city authorities and event organizers. In Rio de Janeiro, it is expected that the first night of samba school parades will be warm and muggy, with temperatures around 27°C, and no immediate rain forecasted. In São Paulo, preparations continue as the city gears up for the second night of its samba parades, with heightened concerns about crowd management amid the expected heat and humidity, which could influence the festivities.