Recent forecasts from the Japan Meteorological Agency and extended models indicate mostly cloudy skies over Tokyo on August 4, 2026, with daytime highs near 28–29°C and overnight minimums expected around 22–23°C. Persistent cloud cover and elevated humidity from the summer monsoon pattern limit radiational cooling after sunset, while light winds and the urban heat island effect anchor nighttime temperatures near historical baselines slightly above the long-term average. Model consensus shows limited spread in low-level moisture and steering flow, creating tight clustering around 22–23°C as the most probable minimum; minor shifts in frontal timing or convective activity could easily push readings one degree lower or higher. Updated JMA guidance and regional ensemble runs in the next 24–48 hours will refine these variables ahead of market resolution.