**Persistent rain and extensive cloud cover are the dominant drivers keeping Zhengzhou’s August 13 maximum temperature tightly constrained near 24–25 °C.** Official forecasts from Chinese meteorological sources project a daytime high of 25 °C under rain, while independent models such as BBC Weather indicate 24 °C amid heavy precipitation and northerly flow. These conditions sharply reduce incoming solar radiation and enhance evaporative cooling, suppressing temperatures well below the seasonal August average of 30–33 °C. The near-even split between 24 °C and 25 °C (both ~48.5 % implied probability) reflects minor ensemble spread in forecast timing and intensity of showers rather than fundamental disagreement. Heavier or more persistent rain would favor the lower outcome by further limiting daytime warming; lighter or delayed precipitation could allow brief breaks of sun and nudge the peak to 25 °C. Higher outcomes above 26 °C carry low probability because sustained cloudiness and moisture advection are expected to persist through the peak heating hours. Updated model runs and official bulletins ahead of the 13th will be the key catalysts for any market movement.