Forecast consensus from the Hong Kong Observatory and multiple models points to a minimum temperature near 27°C on September 26 under a strong subtropical ridge delivering clear, dry conditions with light winds. Daytime highs are expected to reach 32–33°C before overnight radiative cooling brings the low into the upper 20s, consistent with climatological September norms. Trader preference for 26°C over 27°C likely reflects minor model spread in boundary-layer cooling rates and urban heat-island effects at official stations, while probabilities below 25°C remain negligible absent any frontal intrusion or increased cloud cover. Updated HKO guidance and evening model runs will refine the exact minimum before market resolution.