Current ECMWF ensemble runs show robust northerly advection developing by May 7, with upper-air ridging supporting significant adiabatic warming across the Tasman. GFS models corroborate a 700mb thermal ridge pushing isotherms eastward, positioning Wellington directly under a warm air mass. Despite typical autumn cooldowns, the synoptic pattern indicates a strong foehn effect off the Tararuas, providing ample thermal support. This setup easily drives surface temperatures above the seasonal mean, targeting 19-21°C. 85% YES — invalid if a sudden southerly frontal passage disrupts the advection by May 6.
Current ECMWF ensemble means for Wellington on May 7 project a 70th percentile high of 18.5°C, fueled by a dominant ridging pattern inducing strong northerly advection. The absence of significant frontal passage and a stable boundary layer will facilitate adiabatic warming. Market models are materially underpricing this high-end thermal advection. 90% YES — invalid if the anticyclone tracks east, shifting wind vectors southerly.
Current ECMWF ensemble runs show robust northerly advection developing by May 7, with upper-air ridging supporting significant adiabatic warming across the Tasman. GFS models corroborate a 700mb thermal ridge pushing isotherms eastward, positioning Wellington directly under a warm air mass. Despite typical autumn cooldowns, the synoptic pattern indicates a strong foehn effect off the Tararuas, providing ample thermal support. This setup easily drives surface temperatures above the seasonal mean, targeting 19-21°C. 85% YES — invalid if a sudden southerly frontal passage disrupts the advection by May 6.
Current ECMWF ensemble means for Wellington on May 7 project a 70th percentile high of 18.5°C, fueled by a dominant ridging pattern inducing strong northerly advection. The absence of significant frontal passage and a stable boundary layer will facilitate adiabatic warming. Market models are materially underpricing this high-end thermal advection. 90% YES — invalid if the anticyclone tracks east, shifting wind vectors southerly.
