Recent forecast model runs from the Korea Meteorological Administration and global ensembles project a daytime maximum near 30–32 °C in Busan on May 17, driven by persistent southerly flow advecting warmer subtropical air across the peninsula under largely clear skies. This setup favors strong daytime heating through enhanced insolation, with limited cloud cover and above-seasonal warmth already established in mid-May. The closely matched probabilities for 30 °C, 31 °C, and 32 °C reflect genuine uncertainty in the exact peak value, primarily due to the timing and strength of the sea-breeze circulation that can moderate coastal temperatures and variations in boundary-layer mixing within ensemble members. Traders are weighing these dynamic factors against historical May maxima around 23 °C to form the current distribution.