Northeast monsoon conditions established over southern China produced the stable overnight environment that drove near-unanimous trader consensus toward a 26°C minimum in Hong Kong on September 10. Official Hong Kong Observatory guidance and supporting model runs projected a low of 26°C under partly cloudy skies, with northeast winds of 4–5 knots limiting radiative cooling and keeping temperatures within the mid-20s°C range observed at multiple stations. Seasonal norms for early September, combined with dry daytime air and low precipitation probability, reinforced this narrow outcome. A shift in wind patterns, unexpected cloud cover, or revised station data could still alter the recorded value, though current observational consistency leaves little room for deviation.