Forecasts from the Japan Meteorological Agency show cloudy skies with occasional scattered showers over Tokyo on June 20, consistent with the ongoing tsuyu rainy season that brings frequent cloud cover and reduced solar insolation. This setup typically suppresses daytime maxima by limiting surface heating and promoting evaporative cooling from rainfall, favoring highs near 23–24 °C rather than the seasonal sunny-day peaks around 26–28 °C. Subtle differences among leading outcomes hinge on model variations in cloud thickness, shower timing, and boundary-layer moisture, which can shift the daily maximum by 1–2 °C through changes in shortwave radiation and local advection. Recent guidance indicates no strong high-pressure ridge or heat advection that would push temperatures higher, keeping market-implied probabilities concentrated on moderate values supported by these persistent meteorological conditions.