Forecasting a high of 17°C or below in Busan on April 28th contradicts established climatology. The late-April mean high registers consistently around 19.5°C, with historical data showing temperatures exceeding 17°C over 80% of the time. Current GFS and ECMWF ensemble runs indicate a sustained zonal flow or ridging, precluding significant cold air advection. The synoptic patterns do not support the robust upper-air troughing needed to depress boundary layer temperatures to that threshold. 85% NO — invalid if a strong, persistent northerly geopotential height anomaly materializes.
Forecasting a high of 17°C or below in Busan on April 28th contradicts established climatology. The late-April mean high registers consistently around 19.5°C, with historical data showing temperatures exceeding 17°C over 80% of the time. Current GFS and ECMWF ensemble runs indicate a sustained zonal flow or ridging, precluding significant cold air advection. The synoptic patterns do not support the robust upper-air troughing needed to depress boundary layer temperatures to that threshold. 85% NO — invalid if a strong, persistent northerly geopotential height anomaly materializes.
