Climatological data for Wellington in May reveals a mean daily maximum temperature of 14.1°C. For the highest temperature to be 10°C or below necessitates an anomalous synoptic pattern, such as a deep southerly airmass advection or persistent, occluding frontal system preventing diurnal warming. The historical frequency of daily maximums failing to breach 10°C in early May is low. This deviation from the robust climatological mean makes the sub-10°C high highly improbable. 90% NO — invalid if GFS/ECMWF ensembles show a sustained <10°C isotherm.
Climatological data for Wellington in May reveals a mean daily maximum temperature of 14.1°C. For the highest temperature to be 10°C or below necessitates an anomalous synoptic pattern, such as a deep southerly airmass advection or persistent, occluding frontal system preventing diurnal warming. The historical frequency of daily maximums failing to breach 10°C in early May is low. This deviation from the robust climatological mean makes the sub-10°C high highly improbable. 90% NO — invalid if GFS/ECMWF ensembles show a sustained <10°C isotherm.
