Forecast models from agencies and services including GFS, Met Office, and Yr.no indicate a highest temperature of 24–26°C for São Paulo on October 15, driven by persistent cloud cover, scattered thunderstorms, and a shift toward cooler, moister air with high humidity and moderate westerly winds. Recent days have featured warmer maxima near 27–29°C under clearer conditions, but incoming precipitation and reduced solar heating are expected to cap the peak. Market-implied odds favoring 27°C reflect trader assessment of model spread, potential localized variations at the official station, and historical October variability around the 25°C climatological mean, while lower probabilities for 28°C+ align with the consensus for suppressed afternoon warming. Updated model runs and official observations will clarify resolution near market close.