Forecast uncertainty for Chongqing’s daily minimum temperature on September 25 centers on variable cloud cover, light rain chances, and regional airflow patterns that could produce readings clustered in the low-to-mid 20s °C. Current model guidance points to overnight lows near 21–24 °C under partly cloudy to overcast skies with minimal wind, consistent with late-September climatology where average minima hover around 21–22 °C. The near-even market split between an 18 °C-or-below outcome and 28 °C-or-higher reflects trader assessment of small but plausible shifts: stronger nocturnal cooling under clearer skies or localized rain-cooled air masses could push the low below 20 °C, while persistent cloud cover or warmer advection might keep it above 23 °C. Resolution hinges on official station readings at the day’s coldest hour, typically just before dawn. Updated short-range model runs and observational data over the next 48 hours will likely tighten the distribution around the most probable 21–23 °C range.