Recent model consensus from GFS and other global systems points to a strengthening northerly flow and frontal passage over Beijing on October 17, 2026, driving widespread cloud cover, heavy rain, and suppressed daytime heating that caps the maximum near 15–16°C. Persistent overcast skies and precipitation reduce incoming solar radiation while cool advection from higher latitudes limits boundary-layer warming, with surface winds shifting northerly at 10–15 km/h. Ensemble spreads and slight differences in frontal timing create the tight clustering around 16°C and 17°C in market-implied odds, as even modest variations in rainfall onset or wind strength could shift the daily peak by 1°C. Updated runs from the China Meteorological Administration and next 12–24-hour model cycles will refine these thresholds ahead of market resolution.