Trader consensus on a 24°C high for Seoul/Incheon on September 25 rests on official Korean Meteorological Administration guidance and real-time observations showing daytime maxima reaching that level amid persistent cloud cover, light rain, and easterly flow. Multiple forecast models converged on a peak near 24°C (roughly 75°F), consistent with the season’s climatological range of 22–28°C for late September under similar synoptic patterns. With the observation window closing and no late-day warming signals in updated runs, market-implied odds reflect near-certainty in the recorded maximum. Only an unexpected measurement revision or post-closing data adjustment would alter the outcome.