**Recent forecasts for Tokyo show a shift from hot, humid conditions to a cooler, wetter pattern on August 27, driving trader focus on minima near 25–26°C.** Highs earlier in the week reached 33–35°C under mostly clear skies with southerly flow, but models now indicate increasing cloud cover, scattered thunderstorms, and a frontal influence arriving mid-week. This reduces daytime heating while limiting nighttime radiative cooling, with official and ensemble guidance pointing to overnight lows of roughly 23–26°C. Key differentiating factors include the exact timing and coverage of rain (which adds latent heat and traps warmth), wind shifts (northwesterly flow may enhance mixing), and urban heat retention in Tokyo. Higher cloud fractions and sustained precipitation favor the upper end of that range (26°C), while clearer breaks or lighter winds could allow slightly more cooling toward 25°C or below. Short-range model runs remain closely aligned on this band but carry typical uncertainty in precipitation placement and boundary-layer details, which explains the tight clustering of market-implied probabilities around the leading outcomes. Updated JMA and global model guidance over the next 24–48 hours will likely refine these thresholds ahead of resolution.