**Short-term forecast uncertainty for Busan’s maximum temperature on August 17 centers on the timing and intensity of expected afternoon showers amid persistent summer heat.** Korea Meteorological Administration guidance points to a minimum near 24°C and maximum around 32°C under partly cloudy to overcast skies, with 60% precipitation probability in the afternoon. Coastal sea breezes, high humidity from the North Pacific high-pressure ridge, and potential convective development can suppress peak readings by several degrees compared with clear-sky scenarios. Recent model consensus and observational trends support the market’s tight clustering around 27–29°C, as traders weigh the balance between climatological August highs (typically 29–31°C) and the cooling effects of cloud cover or rainfall. Updated short-range model runs and official KMA briefings tomorrow morning represent the next key data points that could shift implied probabilities.