Current Korea Meteorological Administration guidance points to a daytime maximum of 28–30°C in Busan on May 18 under a building high-pressure ridge and southerly flow that favors modest warming. Traders therefore cluster around the 29–31 °C outcomes, with resolution hinging on the precise timing of the daily peak and any last-minute adjustments to short-range model output from the KMA or global ensembles. Busan’s coastal setting typically introduces sea-breeze moderation that caps afternoon temperatures, while clear skies beneath the ridge enhance solar heating and reduce cloud cover that could otherwise limit the high. Historical mid-May climatology for the region shows average maxima near 20–22 °C, so the current setup represents an above-normal warm anomaly driven by persistent southerly advection.