Recent model consensus points to a transient warm air mass over São Paulo driving surface highs near 31–34 °C on 31 August before a stronger cold front arrives overnight, with official guidance from agencies such as INMET and international ensembles showing timing and cloud-cover differences that cap the daily maximum. This setup follows several days of anomalous late-winter heat (recent observations 30–36 °C) well above the 1991–2020 August mean of ~23–25 °C. Trader consensus favoring 29 °C or below as the modal outcome therefore reflects expectations that increased northerly winds, scattered convection, or earlier frontal cooling will prevent the highest forecast values from materializing, while the modest probabilities attached to 32–34 °C capture residual upside risk if the front slows. Updated model runs and local observations over the next 48 hours will sharpen resolution criteria.