Trader consensus for Chengdu’s June 18 peak clusters tightly around 30–31 °C (combined ~57 % implied probability) because early-summer conditions in the Sichuan Basin typically produce highs near the long-term average of 29–30 °C. Persistent high humidity and frequent afternoon convective clouds limit surface heating, while the official measurement at the urban station reflects these moderating effects. Recent model runs show only modest differences in solar exposure or timing of showers that could shift the daily maximum by 1 °C either way, keeping adjacent bins competitive. Later in the month, drier subtropical air can push readings above 33 °C, but mid-June climatology and current basin moisture favor the narrower 29–31 °C range.