**Forecasts from the Japan Meteorological Agency (JMA) and other models indicate a minimum temperature near 24°C for Tokyo on September 1, 2026, under mostly cloudy conditions with light northeast winds and high humidity.** This aligns with the market's strongest implied probabilities for 24°C (45%), 23°C (28.5%), and 25°C (25%), reflecting trader consensus on typical late-summer nocturnal temperatures. Persistent residual heat (残暑) across eastern Japan, driven by high pressure and warm air advection, has kept overnight lows elevated, with recent JMA outlooks projecting minima of 24–25°C. Historical early-September averages for Tokyo hover near 22–24°C, but current model runs show limited overnight radiative cooling due to cloud cover and moisture. No major frontal passages or typhoon influences are expected to arrive in time to drop temperatures below this range before September 1. Upcoming JMA and ensemble forecast updates in the next 24–48 hours will refine the exact minimum, particularly any shifts in cloudiness or wind patterns that could alter the low by 1–2°C. These near-term model adjustments represent the key variables that could shift the tight clustering of probabilities around 23–25°C.