**Forecast consensus for Jinan’s overnight low on August 30 centers on 18–22 °C, producing the tightly matched market probabilities.** Multiple global and regional models project a minimum in this narrow band because the city sits under weak northeasterly flow on the western flank of the subtropical high, with light winds (2–6 km h⁻¹) and partly cloudy to clear skies that allow moderate long-wave radiative cooling after sunset. Key differentiating factors include: - **Cloud cover and timing**: Persistent low-level stratus or scattered clouds can reduce nocturnal cooling by 1–2 °C; clearer periods permit stronger radiative loss and lower minima near 18 °C. - **Boundary-layer moisture and dew-point depression**: Dew points around 15–18 °C limit how far surface temperatures can fall before saturation; drier air aloft enhances cooling. - **Advection and urban heat island**: Gentle northeast winds advect slightly cooler air from the Shandong hills, while Jinan’s urban canopy retains extra heat, raising the observed minimum relative to rural stations. - **Model spread**: Differences between ECMWF, GFS, and CMA runs on the exact timing of clearing and wind shift create the observed 18–22 °C envelope. With no frontal systems or significant precipitation expected, the final recorded minimum will hinge on the precise evolution of these local thermodynamic and radiative processes overnight, keeping implied probabilities clustered around the 18–22 °C outcomes.