Recent East Asian summer heat patterns, with above-average temperatures forecast across southern China including the Sichuan Basin, underpin trader consensus around 37–39°C for Chengdu’s July 19 maximum. The basin’s topography and high humidity trap heat, while model consensus on cloud cover, precipitation timing, and daytime solar heating creates tight spreads between these brackets. Subtle variations in forecast runs—such as afternoon thunderstorm development or wind shifts—can shift the daily peak by 1–2°C, explaining the close market-implied odds. Official observations from the China Meteorological Administration will resolve the market, with traders weighting ensemble guidance and historical analogs for similar late-July conditions.