Recent official forecasts from the Japan Meteorological Agency and supporting models point to a high near 30–31°C for Tokyo on August 31 under a regime of increasing sunshine after morning cloud cover, with light northeasterly winds and high humidity limiting rapid warming. Trader consensus clusters tightly around 29–31°C because the difference hinges on precise afternoon cloud timing and solar insolation under partly cloudy conditions, rather than any synoptic shift or frontal passage. Persistent moisture from prior days’ rain keeps dew points elevated near 22–23°C, moderating peak readings relative to historical late-August norms of 30–32°C, while any earlier clearing could push the maximum toward 31°C. Updated model runs and JMA guidance issued in the past 24 hours remain the key near-term catalysts.