Current forecasts from agencies like the Korea Meteorological Administration place Seoul's overnight low on June 17 near 20°C amid early-summer conditions, with market-implied odds clustered tightly between 19–21°C reflecting modest model spread on exact radiative cooling overnight. Key differentiating factors include variable cloud cover, which reduces nighttime heat loss under clearer skies versus trapping warmth when overcast, alongside light winds, humidity levels near 70–80%, and the urban heat island effect that typically elevates minima by 1–2°C relative to rural baselines. As the jangma monsoon approaches later in the month, increasing moisture and potential showers could limit cooling, while stable high-pressure patterns support the current consensus range; updated model runs in the next 24–48 hours will likely refine these probabilities ahead of resolution.