Recent forecasts from the Korea Meteorological Administration and ensemble models indicate Seoul's overnight low on June 12 will hinge on clear-sky radiative cooling under a high-pressure ridge, with minimal cloud cover and light winds expected to allow temperatures to drop efficiently after sunset. Ensemble spreads show morning lows clustering near 15–17°C, where even modest increases in humidity or a slight shift in the steering flow could limit cooling and push readings to 18°C or higher. Historical June climatology places typical lows around 16–18°C, providing context for why traders see the tightest odds clustered at 17–18°C while assigning lower probability to extremes below 15°C absent an unexpected cold advection event. Updated model runs and KMA briefings in the next 48 hours will refine these variables ahead of market resolution.