**Forecast models from multiple sources, including WeatherBug, Yr.no, and Chinese meteorological outlets, consistently project overnight lows for Chongqing on September 2 in the 21–24°C range, with several runs centering near 22–23°C.** This drives the tight clustering of market-implied probabilities around 20°C (46.5%) and 21°C (51.0%), as traders weigh the most probable minimum against minor model spread. Key scientific factors include strong radiative cooling under mostly clear to partly cloudy skies with light easterly or northeasterly winds (typically 1–5 km/h), which allow surface temperatures to drop efficiently after sunset. High daytime humidity (around 40–60%) and dew points near 19–21°C moderate the decline by limiting how far temperatures can fall before reaching saturation. Chongqing’s basin topography and urban heat island further temper extremes, keeping the overnight minimum above the regional seasonal baseline for early September. No significant cold-air intrusions, frontal passages, or precipitation are indicated in the latest guidance for the immediate period, supporting the consensus that the low will settle near the upper end of the historical early-September range (typically 21–25°C). Slight downward revisions in some ensemble members explain the secondary support for 20°C, while warmer outliers remain lower probability absent unexpected changes in cloud cover or wind. Updated model runs and official briefings from agencies like the China Meteorological Administration will provide the next key data points for resolution.