Recent ensemble forecasts from the Korea Meteorological Administration indicate a transient warm advection pattern that supports peak readings near 29°C for Busan on May 18, driving the 32.5% implied probability on that outcome. Coastal moderation from the East Sea typically caps mid-May highs around 21–23°C, yet current synoptic conditions feature southerly flow ahead of a strengthening high-pressure ridge, producing a positive temperature anomaly. Key variables include afternoon sea-breeze timing, which could shave 1–2°C if onshore winds strengthen earlier than modeled, versus clearer skies that would allow fuller diurnal heating. Traders therefore assign meaningful but secondary probabilities to 30°C and 31°C while discounting sub-27°C outcomes given the limited cooling mechanisms in the latest runs.