The closely matched 43% and 41% implied probabilities for 26°C versus 25°C as Shanghai’s lowest temperature on August 16 reflect genuine short-range forecast uncertainty between major numerical weather prediction models. August climatology in the Yangtze River Delta features high humidity and urban heat retention that typically moderate overnight lows near 25–27°C, with outcomes hinging on variables such as cloud cover, boundary-layer mixing, and any weak frontal passage. Official guidance from agencies like the China Meteorological Administration will refine these projections as new runs become available, allowing traders to assess model consensus shifts ahead of resolution.