Recent forecasts from the Korea Meteorological Administration and models indicate mostly clear skies over Seoul overnight into June 18, supporting minimum temperatures near 20–21°C as the leading outcomes priced equally by traders. Radiative cooling under light winds and moderate humidity levels near 60–70% will determine the exact low, with any increase in cloud cover or southerly flow potentially holding readings at 21°C while clearer conditions favor 20°C. These values align with early-summer climatology before the full onset of the East Asian monsoon, when overnight lows typically range 17–22°C. Updated model runs tonight and early-morning observations from official stations will provide the final data points ahead of market resolution.