**Strong northerly winds and limited overnight radiative cooling are the main drivers positioning 12°C as the leading outcome (60.5% implied probability) for Wellington’s lowest temperature on August 25.** Current model consensus and official guidance show a mild air mass advected from the northwest, with sustained winds of 20–35 mph (gusts higher) expected through the night. These winds, combined with variable high cloud, inhibit surface cooling that would otherwise produce lower minima under clearer, calmer conditions typical of late-winter anticyclones. Recent station data indicate August 2026 has run slightly above the long-term normal (monthly mean 10.5°C versus 10.3°C), with the past week’s overnight lows mostly in the 7–12°C range and no significant cold outbreak developing. Forecasts from multiple sources converge on a minimum near 10–12°C for the night of the 24th–25th, with some guidance as low as 9–10°C if cloud increases or winds ease briefly. The market’s heavy weighting toward 12°C (followed by 11°C at 27% and 10°C at 16.5%) reflects this narrow, well-defined range and the absence of any model support for sub-9°C readings. Traders are effectively pricing the probability that the official minimum will fall at or just below the upper end of the expected window. Updated model runs and MetService guidance over the next 12–18 hours remain the key near-term catalysts.