ECMWF ensemble mean confirms persistent anticyclonic ridging across Tasman. Strong NW flow drives Foehn advection, raising isotherms. High-res models indicate significant pre-frontal warmth. 90% YES — invalid if ridge collapses prematurely.
Wellington's late April climatological mean maximum temperature hovers near 17°C. Achieving 19°C necessitates robust anticyclonic ridging and persistent northerly advection, a less frequent synoptic setup as the Southern Hemisphere transitions deeper into autumn. Historical data for April 29 rarely breaches this 80th percentile threshold, indicating a low-probability thermal anomaly. The signal is clear: fundamental climatology dictates sub-19°C. 90% NO — invalid if a persistent Tasman Sea high develops by April 26.
ECMWF ensemble mean confirms persistent anticyclonic ridging across Tasman. Strong NW flow drives Foehn advection, raising isotherms. High-res models indicate significant pre-frontal warmth. 90% YES — invalid if ridge collapses prematurely.
Wellington's late April climatological mean maximum temperature hovers near 17°C. Achieving 19°C necessitates robust anticyclonic ridging and persistent northerly advection, a less frequent synoptic setup as the Southern Hemisphere transitions deeper into autumn. Historical data for April 29 rarely breaches this 80th percentile threshold, indicating a low-probability thermal anomaly. The signal is clear: fundamental climatology dictates sub-19°C. 90% NO — invalid if a persistent Tasman Sea high develops by April 26.
