Forecast models show considerable uncertainty in Chongqing’s overnight minimum on October 2, with most guidance placing the low between 18–21 °C amid persistent cloud cover, light rain, and weak easterly flow. This narrow range explains the near-even market split between 15 °C or below (47 %) and 25 °C or higher (46.5 %), as small differences in cloud timing or boundary-layer moisture can shift the minimum by 2–3 °C through altered long-wave radiative cooling. Historical early-October climatology (average low near 16–17 °C) and current China Meteorological Administration runs support a mild outcome, yet ensemble spread leaves room for either cooler clearing or warmer trapped humidity. Updated model runs and local observations tonight will be the key catalyst for any sharp shift in implied probabilities.