Current Korea Meteorological Administration forecasts point to a daytime high of 28–30°C in Busan on May 18 under a strengthening high-pressure ridge and southerly flow that supports modest warming. Busan’s coastal setting typically moderates peaks through afternoon sea breezes, keeping temperatures near the upper end of mid-May climatology rather than allowing sharper spikes. Model guidance shows tight clustering around this range, with minor differences arising from exact timing of onshore winds or brief cloud cover that could shave a degree off the maximum. Traders appear to weigh these variables nearly evenly between 29°C and 30°C, reflecting the narrow forecast spread and the resolution source of official station observations at Gimhae International Airport.