NWM ensemble output, particularly ECMWF, strongly biases towards sub-15°C lows for Seoul on May 10. A reinforcing high-pressure system tracks in post-frontal passage on May 9, establishing clear skies and minimal advection overnight, maximizing radiative cooling potential. GFS 06z run 850hPa temps indicate a cooler airmass in place, with surface lows consistently projected 12-14°C. Market is underpricing the diurnal temperature range under such synoptic conditions. 95% YES — invalid if significant cloud cover or sustained southerly flow develops post-May 8.
NWM ensemble output, particularly ECMWF, strongly biases towards sub-15°C lows for Seoul on May 10. A reinforcing high-pressure system tracks in post-frontal passage on May 9, establishing clear skies and minimal advection overnight, maximizing radiative cooling potential. GFS 06z run 850hPa temps indicate a cooler airmass in place, with surface lows consistently projected 12-14°C. Market is underpricing the diurnal temperature range under such synoptic conditions. 95% YES — invalid if significant cloud cover or sustained southerly flow develops post-May 8.
