**Forecast models and official outlooks place Zhengzhou’s September 29 minimum near 17–19 °C, producing the near-even market split between the 18 °C outcome and lower bins.** Local meteorological guidance and multiple numerical forecasts (including GFS-derived products) converge on a low of roughly 17–18 °C under partly cloudy to clear skies following overnight radiative cooling after the 28 September rain. Light southwesterly winds and dew-point values in the mid-teens limit further cooling, while any localized clear patches or slightly higher humidity could push readings to 16 °C or below. Traders appear to be weighting the central forecast against the realistic spread in station measurements and model timing, keeping the 18 °C and sub-16 °C probabilities tightly matched. Updated overnight observations and final official station data will resolve the market.