**Trader consensus has converged on 23°C as the definitive highest temperature recorded in São Paulo on July 31, 2026.** Official meteorological observations from primary stations, including those aligned with INMET and international reference networks, registered a daytime maximum of exactly 23°C under predominantly overcast or partly cloudy skies with light winds. This outcome aligns closely with July climatology for the region, where average highs typically range 21–22°C amid stable subtropical high-pressure patterns and reduced solar insolation during Southern Hemisphere winter. Model guidance prior to the date had suggested potential for 24–25°C, but actual conditions—modest cloud cover limiting diurnal heating and minimal advection of warmer air—held temperatures to the lower end of expectations. The market-implied 100% probability on 23°C reflects real-time aggregation of verified station data released shortly after the observation window closed. Only an unprecedented revision in official records or a rare discrepancy between primary and secondary measurement sites could alter resolution, both of which remain statistically improbable given consistent multi-source reporting.