Recent numerical weather prediction runs from major models including GFS and ECMWF show maximum temperatures in Shanghai on August 4 clustering tightly between 34–35 °C, producing the near-even market split. Subtle differences hinge on afternoon cloud cover, boundary-layer mixing, and urban heat-island amplification amid persistently high humidity and weak steering flow typical of the East Asian monsoon. Recent days of above-normal heat have primed the surface for strong diurnal warming, while any increase in low-level moisture or thin cirrus could cap the peak at 34 °C; clearer skies would favor 35 °C. Updated model cycles and official Shanghai Meteorological Service guidance ahead of the date remain the key variables traders are monitoring.