**Latest forecast guidance from models such as GFS positions the overnight minimum in Tokyo on October 14 near 19–20 °C, supporting the market’s strong consensus on those two outcomes.** Clearing skies after earlier showers, combined with northerly winds and building high pressure, are promoting radiative cooling through the night, with dew points falling into the mid-teens. This aligns with the seasonal shift toward cooler autumn conditions, though October 2026 has so far run warmer than the 1991–2020 baseline. Traders are weighting real-time observational updates and the final Japan Meteorological Agency reading, which resolves the market once the daily minimum is confirmed.