Forecast models from sources like the National Meteorological Center and international ensembles indicate Jinan’s overnight minimum on September 17 will likely settle near 20 °C, driven by persistent cloud cover that limits radiative cooling and light southwesterly winds averaging 2–4 m/s. These conditions suppress the sharp temperature drop typical of clear autumn nights in the North China Plain, where September climatology shows average lows around 18 °C. Trader sentiment clusters around 17–18 °C outcomes because recent model runs have trended slightly cooler than earlier guidance, while the near-even odds on 12 °C or below reflect low-probability scenarios requiring an unforecast cold surge. Official station data from the China Meteorological Administration, due within hours of midnight local time, will resolve the market under standard 24-hour minimum criteria.