ECMWF extended runs for late April indicate a robust Tasman high, driving strong northerly warm air advection into Wellington's boundary layer. Forecasted maximum temperatures consistently model +3°C to +4°C anomalies above the April climatological mean of 16.5°C. Diurnal heating under projected clear skies will be efficient. This synoptic pattern offers a high probability of breaching the 20°C threshold. 90% YES — invalid if mid-latitude trough accelerates and brings a southerly shift by April 28.
ECMWF extended runs for late April indicate a robust Tasman high, driving strong northerly warm air advection into Wellington's boundary layer. Forecasted maximum temperatures consistently model +3°C to +4°C anomalies above the April climatological mean of 16.5°C. Diurnal heating under projected clear skies will be efficient. This synoptic pattern offers a high probability of breaching the 20°C threshold. 90% YES — invalid if mid-latitude trough accelerates and brings a southerly shift by April 28.
