**Balanced market-implied odds around 50% for a Moscow low of 2°C or below versus 49% for 12°C or higher on October 17 reflect substantial short-range forecast uncertainty amid the autumn transition.** Ensemble model spreads arise from variable jet-stream positioning and competing air masses, where northerly Arctic outbreaks could drive rapid overnight cooling below seasonal norms of roughly 3°C, while southerly or Atlantic flows moderate temperatures toward 8–10°C. Current guidance from multiple sources clusters overnight lows near 8°C under partly cloudy, light-wind conditions, yet the tight clustering of single-degree bins near 34% underscores how small shifts in cloud cover, wind, or frontal timing can alter the minimum. Roshydromet updates and next ECMWF/GFS runs will likely narrow the range before resolution.