Current GFS and ECMWF 00z ensembles show high confidence in Seoul's Tmin dipping below 12°C on April 28. The synoptic pattern indicates a post-frontal cold air advection (CAA) following a transient zonal flow, establishing a brief but strong high-pressure ridge. This setup, coupled with anticipated clear-sky conditions and diminishing wind shear in the boundary layer, will facilitate significant radiative cooling overnight. 850mb isotherm analysis consistently projects temperatures in the +1°C to +4°C range, which, when coupled with a stable nocturnal boundary layer, readily supports surface lows in the 8-10°C band. No significant warm air advection (WAA) or extensive cloud cover is indicated by probabilistic forecasts to mitigate this effect. Sentiment: Local Korean meteorological forums are largely anticipating a cooler than average morning low. [90]% YES — invalid if dominant cloud cover persists through night or significant WAA develops.
Current GFS and ECMWF 00z ensembles show high confidence in Seoul's Tmin dipping below 12°C on April 28. The synoptic pattern indicates a post-frontal cold air advection (CAA) following a transient zonal flow, establishing a brief but strong high-pressure ridge. This setup, coupled with anticipated clear-sky conditions and diminishing wind shear in the boundary layer, will facilitate significant radiative cooling overnight. 850mb isotherm analysis consistently projects temperatures in the +1°C to +4°C range, which, when coupled with a stable nocturnal boundary layer, readily supports surface lows in the 8-10°C band. No significant warm air advection (WAA) or extensive cloud cover is indicated by probabilistic forecasts to mitigate this effect. Sentiment: Local Korean meteorological forums are largely anticipating a cooler than average morning low. [90]% YES — invalid if dominant cloud cover persists through night or significant WAA develops.
