Recent forecast guidance from the Korea Meteorological Administration and ensemble models indicates a stable overnight pattern for Seoul on June 19, with light winds, partial cloud cover, and surface temperatures holding near 20–21 °C, aligning with the market’s leading probabilities. This reflects the typical early-summer climatology of rising nocturnal minima (historical June lows averaging ~19 °C) tempered by current high-pressure influence that limits radiational cooling. Key differentiating variables include exact dew-point recovery, boundary-layer mixing, and any late-day convective remnants that could nudge the minimum by 1 °C. Traders are weighting the narrow spread between 20 °C and 21 °C outcomes because model runs converge on this range, while lower probabilities on 19 °C or 22 °C reflect tail risks from forecast adjustments expected in the final 24-hour updates.