During the 2023 Brazilian Carnival holiday weekend, record-breaking rainfall—reaching in 24 hours—caused deadly floods and landslides across the state of São Paulo. At least 64 people were killed, of which 63 were in São Sebastião. Background The affected regions of São Paulo are located in coastal communities surrounded by mountains. On 18–19 February 2023, an area of low pressure off the coast of Brazil brought moist onshore flow, leading to significant rainfall in the region. The São Paulo mountains enhanced the rainfall through orographic lift. A total of fell in just 24 hours in Bertioga just outside of São Sebastião. The city observed in the same period. Other significant totals include in Guarujá, in Ilhabela, and in Ubatuba. The rainfall in Bertioga was the greatest such total in a 24-hour span on record in the country. This far exceeded the previous record of on 15 February 2022, which caused deadly floods in Petrópolis. Meteorologists at MetSul Meteorologia suggested this could be among the highest non-tropical cyclone rainfall totals in the world. Further rains on 21 February exacerbated conditions. The local meteorological agency warned of further rains on 22 and 23 February. Impact The prolific rains caused a cascade of landslides and mudslides across São Paulo, with the city of São Sebastião being especially hard-hit. As of 21 February, authorities confirmed 44 fatalities, with 43 of those in São Sebastião and the rest in Ubatuba. A further 23 people suffered injuries, six seriously, and dozens of people remain missing. At least 50 homes were destroyed in São Sebastião. At least 2,496 people were displaced or left homeless. The Rio-Santos highway, the main road in the region connecting it to Rio de Janeiro state, suffered extensive damage, with numerous landslides covering or destroying stretches of the road. Another road connecting Santos with Bertioga was blocked off. Landslides from the rainfall on 21 February impacted Juqueí, displacing 80 people. Wind exceeding and waves of more than prompted the closure of the Port of Santos on 18 February. Response Local emergency management agencies quickly dispatched more than 100 firefighters for search and rescue operations. By 21 February, more than 600 personnel from the Government of the State of São Paulo, the Brazilian Army, the Federal Police, the municipal government of São Sebastião, and volunteers were on the ground searching for survivors. A two-year-old and a mother in the middle of giving birth were rescued