Current atmospheric conditions over southeastern Brazil, including a stable high-pressure system and reduced moisture advection from the Atlantic, are driving daytime maximum temperatures in São Paulo toward 22°C on May 17, aligning with the market-implied consensus. This outcome matches long-term climatological averages for mid-autumn, when regional temperatures typically range from 17–23°C under clear skies and light winds, with no significant warm-air intrusion or urban heat-island amplification evident in recent National Institute of Meteorology observations. Model consensus from global ensembles reinforces limited diurnal heating potential through the afternoon. A rapid shift in steering winds or localized convective warming could push readings above 23°C, though such deviations remain statistically uncommon this late in the season.