Latest ensemble forecasts from global models like ECMWF and GFS, corroborated by the Korea Meteorological Administration, project Seoul's March 27 high temperature clustering around 15°C, fueling its 36% implied probability as traders price in a mild high-pressure ridge over the Korean Peninsula. This edges out 16°C or higher at 32.5% amid model spread reflecting uncertainties in cloud cover and southerly winds, which could push peaks upward by 1-2°C. Historical data shows March 27 maxima averaging 12°C since 1991, but an anomalously warm early spring—driven by transient Arctic Oscillation shifts—elevates warmer outcomes over cooler ones like 9-14°C, despite 16.5% odds each, as diurnal heating thresholds differentiate tight races. Traders eye tomorrow's 12Z updates for resolution catalysts.