**Trader consensus centers on a 7°C minimum for Wellington on September 13, 2026, with overwhelming market-implied odds of 99.5%.** This reflects alignment across official forecasts from MetService and other monitoring sources, which project overnight radiative cooling under clearing skies and light southerly winds easing to variable or calm conditions. Current observations show daytime highs near 15°C with partly cloudy skies transitioning to clearer periods, allowing temperatures to fall steadily through the evening toward the expected low. Supporting evidence includes consistent model outputs and station data indicating the overnight minimum will settle at or very near 7°C, consistent with typical early-spring climatology for the region under a building high-pressure influence. Minor outcomes like 8°C or lower values carry negligible odds because they would require notable deviations such as increased cloud cover suppressing cooling, stronger winds mixing the boundary layer, or localized microclimate effects at the official recording site. Realistic challenges remain limited given the advanced hour and forecast stability, but unexpected changes in wind direction or thicker low-level cloud could nudge the recorded low slightly higher or, less likely, allow brief further cooling. The market’s near-certainty mirrors the narrow uncertainty range in the latest guidance from authoritative New Zealand meteorological agencies.