Tight clustering of market-implied probabilities around 28–30°C reflects consensus from leading weather models like ECMWF and GFS, which project afternoon highs in this range for São Paulo on March 23 amid lingering summer warmth and moderate humidity. Recent forecast updates from Brazil's INMET indicate a peak near 29°C, driven by light southerly winds tempering urban heat island effects, though slight variations stem from uncertainty in convective cloud development—potentially capping temperatures at 28°C or pushing to 30°C+ with clearer skies. Historical March averages hover at 27–29°C, but ensemble spreads of 1–2°C underscore trader caution, with no major cold fronts disrupting the mild tropical pattern.