The Hong Kong Observatory’s official minimum temperature reading of exactly 23 °C for May 16 drives the market’s near-certain consensus on that outcome. Daily minimums are measured at standard Stevenson-screen stations under World Meteorological Organization protocols, capturing the lowest air temperature recorded between midnight and midnight local time. In mid-May, regional climatology typically produces overnight lows near 24 °C under prevailing southeasterly flow and high humidity, so the observed 23 °C sits squarely within expected seasonal variability. No major frontal passages or anomalous radiative cooling events occurred that day to push readings lower. Only a post-event station calibration revision or redefinition of the observation period could alter the final figure, both of which are exceedingly rare once the daily summary is published.