Recent forecasts from meteorological models and Brazil’s INMET indicate a cold front advancing across the Southeast, advecting cooler polar air and increasing cloud cover over São Paulo, which limits daytime radiative heating and positions maximum temperatures near 17–19°C on June 15. Seasonal climatology shows June highs averaging 21–22°C, yet the frontal passage has already produced observed maxima around 18–21°C in early June, pulling market-implied probabilities toward the lower end of the normal range. Numerical weather prediction consensus highlights modest model spread on exact peak values, with rain-cooled boundary layers favoring 18°C as the modal outcome while leaving room for minor shifts if steering flow or insolation changes before resolution.