Recent heatwave conditions across South Korea, with official alerts for extreme temperatures exceeding 40°C earlier in August, have elevated baseline warmth and sustained high-pressure dominance, pushing trader consensus toward 32–33°C as the most probable peak for Seoul/Incheon on August 12. Korea Meteorological Administration short-range guidance and ensemble model outputs highlight modest day-to-day variability driven by differences in cloud cover, boundary-layer mixing, and weak easterly flow that could either enhance or suppress afternoon heating by 1–2°C. Incheon’s coastal location introduces additional uncertainty through potential sea-breeze moderation compared with Seoul’s urban heat-island amplification. With probabilities tightly clustered between 31–34°C, markets reflect genuine forecast spread in maximum temperature resolution criteria rather than a dominant signal, pending updated model runs closer to the date.