Recent forecasts from the Korea Meteorological Administration place Busan’s peak temperature on May 17 squarely in the 30–32 °C range, producing the tightly clustered market odds. Clear skies and persistent southerly flow are advecting warmer subtropical air while maximizing daytime solar heating. Numerical weather prediction models converge on these values, with minor spread arising from subtle differences in predicted boundary-layer mixing and the precise timing of peak insolation. Above-seasonal mid-May warmth has already lifted daytime maxima several degrees above the long-term climatological average, leaving only narrow uncertainty between the 30 °C, 31 °C, and 32 °C outcomes.