Recent Japan Meteorological Agency forecasts and ensemble models indicate a minimum temperature of 24–25°C for Tokyo on August 22, 2026, under mostly cloudy skies with scattered showers, light southerly flow, and persistent subtropical high pressure. These conditions, combined with humidity above 75% and the urban heat island effect that retains daytime warmth, strongly limit nocturnal radiative cooling and keep overnight lows clustered near seasonal norms of 23–25°C. Market-implied odds favor 25°C as the most probable outcome because recent model runs show limited variability and no major frontal systems or typhoon influences to alter the pattern before resolution. Updated JMA guidance and fresh observational data expected on August 21 will provide the next key input for traders assessing any shifts in the 24–26°C range.