The Hong Kong Observatory's official forecast of a 26–32°C range for October 13 under fine, dry conditions and light winds provides the primary driver for the 97.5% market-implied probability on a 26°C low. A moderating northeast monsoon combined with an anticyclone aloft has produced stable high pressure, limiting overnight radiative cooling and supporting minimum temperatures near the seasonal norm for mid-October. Recent observations of sea surface temperatures around 28°C and soil temperatures near 30°C further reinforce limited diurnal drops. While numerical weather models show strong consensus, unexpected increases in cloud cover, wind shifts, or localized precipitation could allow the actual minimum to dip to 25°C or lower.