Robust ECMWF/GFS ensemble clustering indicates significant geopotential height amplification over southern China by April 27. This high-pressure ridge will drive potent thermal advection, pushing 850hPa temperatures consistently above 19°C. With strong diurnal insolation and Hong Kong's urban heat island effect, surface temperatures will easily exceed 28°C. This is a high-confidence synoptic thermal signal. 85% YES — invalid if a sudden frontal passage occurs post-25th.
Robust ECMWF/GFS ensemble clustering indicates significant geopotential height amplification over southern China by April 27. This high-pressure ridge will drive potent thermal advection, pushing 850hPa temperatures consistently above 19°C. With strong diurnal insolation and Hong Kong's urban heat island effect, surface temperatures will easily exceed 28°C. This is a high-confidence synoptic thermal signal. 85% YES — invalid if a sudden frontal passage occurs post-25th.
