Current forecasts from the Japan Meteorological Agency and models indicate Tokyo's July 6 low will likely fall between 20–22°C amid lingering tsuyu (plum rain) conditions, with patchy rain, high humidity near 75–80%, and daytime highs around 25°C limiting nocturnal radiative cooling. These factors, combined with urban heat retention and above-normal sea-surface temperatures, support the tight clustering of market-implied probabilities around 18–23°C. Minor differences in cloud cover duration, wind patterns, or precipitation timing across ensemble runs can shift the exact minimum by 1–2°C, explaining why outcomes like 21°C (40%) and 19–22°C (31–35%) remain closely matched with no dominant signal yet. Updated model guidance and official briefings in the next 48 hours will likely narrow this range before resolution.