Forecast models from the Hong Kong Observatory and international agencies currently converge on a daily maximum of 27–28°C for May 18, reflecting the typical late-spring transition into the rainy season in Hong Kong’s subtropical climate. Persistent high humidity, variable cloud cover, and the potential for scattered showers or thunderstorms remain the main variables that could suppress or slightly elevate the peak reading. Recent seasonal outlooks indicate normal to above-normal temperatures through May, consistent with the market’s tight clustering around these two outcomes, while shorter-range guidance shows only modest day-to-day fluctuations. Updated numerical weather predictions and the final Hong Kong Observatory bulletin expected in the next 24–48 hours will likely determine whether traders favor the lower or higher of the two leading bins.