Current meteorological observations and short-range forecasts from the Korea Meteorological Administration indicate that Busan’s daytime high on May 20 will reach exactly 19 °C, driven by persistent cloud cover, light-to-moderate precipitation, and steady onshore flow that suppresses solar heating. These synoptic conditions align with historical May patterns when marine air advection keeps coastal maxima near the seasonal average rather than allowing typical late-spring warming. Trader consensus has converged on the 19 °C outcome because official station data provide a reliable, verifiable benchmark for market resolution, with only narrow uncertainty from minor timing shifts in the rain shield. Clearer skies or a temporary wind shift could still permit brief additional heating before sunset, though current model guidance shows low probability of such change before the daily maximum is recorded.