Recent forecast guidance from the Japan Meteorological Agency points to a minimum temperature near 14–15°C in Tokyo on May 24, driven by partly cloudy skies that allow moderate overnight radiative cooling under a building subtropical high. Numerical models show light winds and dew points around 12°C limiting further drops, while the absence of strong cold advection keeps values above the seasonal low-end range of 11–12°C. Historical May minima average 15°C, but recent model runs have trended slightly cooler as a weak frontal boundary approaches from the north. Traders appear to weigh these variables against the narrow resolution window, with implied probabilities clustered tightly between 13°C and 16°C reflecting both forecast uncertainty and the single-degree granularity of the contracts.