**A warm, dry air mass over southeastern Brazil is driving elevated temperatures across São Paulo ahead of a cold front and rain expected after September 1.** Official and model guidance from sources such as INMET-influenced outlooks and Meteoblue indicate clear to partly cloudy skies with light northwesterly winds and very low humidity (often below 30-40%), which favors strong daytime heating under subtropical high pressure. This setup has already pushed recent highs above 30°C, with August 29 forecasts clustering in the low-to-mid 30s Celsius—consistent with the market’s heaviest weighting on 33–34°C outcomes. Typical August maxima average near 22–23°C, so the current anomaly stems from persistent warm advection and minimal cloud cover or precipitation. Model spreads show some variation (31–36°C), reflecting minor differences in timing of peak insolation and boundary-layer mixing, but the consensus supports a peak in the low-to-mid 30s. Traders’ implied probabilities align with this evidence-based range, as the warm spell is expected to peak before the seasonal shift. No major updates have altered the outlook in the past 24–48 hours.