**Recent heavy rainfall and associated cold air advection into western Chongqing are the main drivers narrowing trader focus to minimum temperatures between 21–24°C for August 29.** Official forecasts from sources including the Chongqing Meteorological Service and global models indicate widespread showers or thunderstorms overnight, with totals potentially reaching 15–80 mm in western districts. This enhances evaporative cooling and reduces nighttime radiative losses under increased cloud cover, while light winds limit mixing. Uncertainty arises from slight differences in model timing of peak rainfall and boundary-layer moisture, which can shift the overnight low by 1–3°C. Chongqing’s basin topography and urban heat island effect further modulate local readings, keeping outcomes tightly contested as fresh model runs and observational updates arrive.