Current meteorological forecasts indicate Wellington's highest temperature on May 18 will most likely settle at 14°C or 15°C, consistent with the market's leading implied probabilities of 55.5% and 35.5%. These figures align with typical late-autumn conditions, where long-term climate normals from NIWA place average daily maxima near 14°C amid moderate westerly flow and stable high pressure. Ensemble model runs show limited variability, with no incoming cold fronts or significant warming expected, keeping the narrow 13–15°C band favored. Traders are weighting the historical rarity of extremes in May—maxima above 16°C or below 12°C occur infrequently—while monitoring the next forecast update for any shifts in the steering pattern.