Diverging short-range forecast models on nocturnal radiative cooling under clear skies and light northerly flow drive the near-even split in Guangzhou's October 7 minimum temperature odds. Recent weak cold-air intrusions have enhanced boundary-layer mixing and lowered dew points, creating uncertainty between typical early-autumn values near 20–22 °C and rarer advective drops toward 14 °C or below. Ensemble spreads highlight sensitivity to wind speed, cloud cover, and humidity; stronger northerlies favor the lower tail while calm conditions support the 24 °C+ cluster. Updated high-resolution runs and official Guangzhou Meteorological Bureau guidance expected in the next 24–48 hours will likely narrow the range ahead of market resolution.