Recent JMA and international model runs indicate Tokyo will see partly cloudy to overcast skies with scattered showers and thunderstorms on August 13, moderating peak heating and favoring a maximum near 28–29 °C. High humidity and weak steering flow limit strong diurnal rises, while any breaks in cloud cover or delayed convection could briefly push readings to 30 °C. These conditions align with climatological late-summer norms of 31 °C daytime highs tempered by frequent moisture. Trader consensus clusters tightly on 28–29 °C because ensemble guidance shows low spread on instability timing, with only modest upside risk if subsidence strengthens. Updated model runs and JMA briefings in the next 24–48 hours will refine precipitation probability and thus the final maximum.