Recent model guidance points to the northeast monsoon arriving near October 1, shifting Hong Kong from hot anticyclonic conditions to easterly flow that favors cloudier skies and scattered showers on the 2nd. This transition caps daytime heating, with official outlooks centering urban highs near 28–31 °C amid 60–90 % humidity and light-to-moderate easterlies. Persistent cloud and precipitation reduce solar insolation relative to late-September peaks, aligning with climatological October averages around 29 °C while introducing day-to-day variability tied to shower timing and monsoon strength. Traders weigh these factors against historical extremes and the Hong Kong Observatory’s next forecast updates, which will refine the precise maximum before market resolution.