Current numerical weather prediction models from the China Meteorological Administration and global ensembles indicate overnight lows for Beijing on September 28 in the 15–17°C range under mostly cloudy skies and light southerly flow, limiting radiative cooling. Trader sentiment remains nearly evenly split between sub-9°C and 18°C+ outcomes because small differences in cloud cover, boundary-layer mixing, and the timing of any weak frontal passage can shift the minimum by several degrees. Recent cooling from a passing system has set a lower baseline than mid-September norms, yet persistent southerly advection and model spread on nocturnal cloud trends sustain the balanced probabilities ahead of final 24-hour guidance updates.