**Trader sentiment for Beijing's July 5 maximum temperature centers on uncertainty in short-term forecast models regarding thunderstorm timing and coverage.** Current guidance from regional models shows scattered thunderstorms and cloud cover persisting into July 5, which typically caps daytime highs by 2–4 °C through reduced solar insolation and evaporative cooling. This keeps the market-implied distribution tightly clustered around 29–31 °C, consistent with climatological July averages of 31–32 °C and recent observed maxima near 35–36 °C under clearer conditions. Differentiation among the leading bins hinges on precise rainfall onset, boundary-layer moisture, and steering flow that could either allow brief clearing for 32–33 °C or sustain overcast skies for 28–29 °C. Official Beijing station readings at 14:00 local time will resolve the market, with traders weighing ensemble spread in the latest model runs for any shifts in convective timing.