Recent forecasts from the Japan Meteorological Agency and extended models indicate Tokyo highs near 25–28°C for June 17, aligning with the closely matched market probabilities around 25–26°C. The onset of the tsuyu rainy season introduces variable cloud cover and scattered showers that can suppress peak temperatures by limiting solar heating, while seasonal outlooks project above-normal warmth across Japan. Ensemble guidance shows modest spread due to steering patterns and precipitation timing, with historical June averages near 26°C providing a baseline. Traders appear to weigh these near-term uncertainties, as updates to short-range models or observed rainfall could readily shift implied odds between the leading outcomes.