A developing tropical cyclone (Noul) east of the Philippines, forecast by the Hong Kong Observatory to intensify and track toward the Guangdong coast, is the dominant driver behind trader sentiment for Hong Kong’s July 27 minimum temperature. Model consensus points to the system weakening into a tropical depression by July 27, delivering widespread cloud cover, heavy rain, and gusty winds that suppress daytime heating while limiting nocturnal cooling. This setup favors overnight lows near 25–26°C, aligning with the closely matched leading market outcomes, though slight variations in the storm’s exact track or intensity could shift the minimum by 1–2°C. Historical July climatology shows typical minimums around 26–28°C, but the active monsoon trough and cyclone activity introduce greater uncertainty in short-range forecasts from the Hong Kong Observatory and global models. Updated NHC and HKO guidance expected over the next 48 hours will likely refine probabilities as the system nears.