On Saturday, a significant rainfall in São Paulo impacted carnival festivities, particularly the megabloco of Alceu Valença held at Ibirapuera Park in the southern part of the city. Many attendees chose to leave the event before it officially began due to the inclement weather. This situation was compounded by flooding in other areas, including Vila Madelena and the city center, where waterlogged conditions discouraged crowds from participating in the celebrations.

The Civil Defense agency alerted that during instances of heavy rain and lightning throughout the street carnival, production teams and block organizers are required to cooperate to ensure public safety. The intense rainfall led to the city of São Paulo being on alert for flooding between 2:25 PM and 5:00 PM, according to the city’s Climate Emergency Management Center. This proactive communication highlights the city's efforts to manage large public gatherings during adverse weather conditions.

In particular, the Terminal Bandeira area downtown was severely affected by flooding, disrupting traffic and accessibility. The Vila Madelena neighborhood reported at least one location rendered impassable due to the water accumulation. These events underscore the challenges of hosting large public festivities in urban environments where weather unpredictability can significantly impact attendance and safety during peak celebratory periods like Carnival.