MetService's latest forecast pins Wellington's highest temperature today at 13°C, aligning with trader consensus at 99.9% implied probability, as southerly winds usher in a cool, stable maritime air mass, capping diurnal warming under persistent cloud cover. Morning observations at Wellington Airport logged starts near 10-11°C, with minimal insolation and shear limiting convective heating, consistent with NIWA model runs showing peaks in the low teens. Historical May averages hover around 14°C, but today's synoptic pattern—featuring a blocking high to the south—mirrors cool analogs from recent autumn days. A realistic challenge would require unexpected clearing and northerly wind shifts late afternoon, though forecast ensembles deem this low-likelihood before resolution at midnight. Traders await final airport observations for confirmation.