Recent model consensus from the Korea Meteorological Administration and global ensembles points to a peak daytime high near 30–31°C in Busan on August 12, shaped by the persistent North Pacific High ridge advecting warm, moist southerly flow while coastal sea breezes and variable afternoon cloud cover introduce modest cooling. With the market split between 31°C (39%) and 30°C (30%), traders are weighing subtle differences in forecast timing of scattered showers versus clearer skies, as even minor shifts in boundary-layer moisture or wind direction can cap or boost the daily maximum by 1–2°C. Historical August climatology for Busan shows mean highs around 29–30°C, so current guidance sits slightly above average yet remains within typical model spread two days out; updated KMA runs and ensemble plumes expected over the next 24–48 hours will likely resolve the narrow gap between these leading outcomes.