Recent ensemble forecasts for Chengdu place the June 29 high near 28–30 °C, consistent with the market’s tight clustering on those bins. The dominant controls are the early East Asian monsoon transition, high regional humidity in the Sichuan Basin, and variable cloud cover from scattered showers or thundershowers that reduce insolation. Persistent overcast or convective rain tends to cap readings near 27–28 °C, while partial clearing under light northeasterly flow allows greater daytime heating toward 29–31 °C. Model spreads remain narrow given the absence of a strong subtropical ridge, aligning with historical June climatology of 28–31 °C averages. Updated runs from global and regional models ahead of the date will be the key near-term catalyst for any shift in implied probabilities.