**The dominant 97.5% market-implied probability for a 19°C low on October 14 reflects post-event confirmation from São Paulo meteorological observations, including ClimaTempo and aligned station data showing overnight temperatures bottoming at 19°C amid light rain, high humidity near 86–98%, and light winds.** This outcome aligns with springtime patterns where regional cloud cover and moisture from recent showers limited radiative cooling, preventing drops toward the historical October average low near 16–17°C. Model runs and real-time reports consistently captured the same threshold without significant divergence. A lower reading would require an outlier station measurement or revised official dataset, scenarios with low likelihood given the convergence across monitoring networks.