Recent numerical weather prediction runs from agencies including the Korea Meteorological Administration indicate a daily maximum in Seoul likely settling near 26–27°C on June 13, driven by partly cloudy skies, light southerly flow, and moderate humidity levels typical of early summer before full monsoon onset. These closely matched market odds reflect genuine forecast spread arising from small variations in afternoon cloud timing, boundary-layer mixing, and the precise strength of any weak frontal passage that could shave or boost the peak by 1°C. Historical June climatology places average highs near 27–29°C, providing context for why traders assign limited probability to outcomes above 29°C or below 25°C given current stable synoptic patterns. Updated model guidance expected within the next 24–48 hours will likely tighten the range ahead of market resolution.