Trader sentiment clusters tightly around 29–31°C for São Paulo's March 26 high, driven by the latest INMET and ECMWF ensemble forecasts projecting peaks of 29.5–30.5°C amid persistent subtropical high pressure favoring afternoon heating. Differentiating factors include minor divergences in model physics: GFS emphasizes urban heat island amplification in the city's concrete sprawl, nudging toward 31°C, while ICON accounts for potential sea breeze incursions from the Atlantic, capping at 29°C—both within observed historical March variability of 27–32°C. Low humidity (40–50%) and minimal cloud cover from outgoing frontal systems heighten uncertainty, with traders pricing 33.5% odds on exactly 30°C as the consensus median amid 1–2°C error margins typical for short-range tropical forecasts.