**Trader consensus centers on a highest temperature of 28°C (46.5% implied probability) for Seoul/Incheon on September 2, 2026, with 27°C (27%) and 29°C (19.5%) as the next most likely outcomes.** This distribution reflects tight clustering in the latest numerical weather prediction outputs around a late-summer maximum near 28°C. Multiple forecasts from sources including the Korea Meteorological Administration, ECMWF-influenced models, and operational guidance for Incheon International Airport indicate a daytime high of 27–29°C under partly cloudy to overcast skies, light southwesterly winds (around 3–5 m/s), and modest humidity levels that support gradual daytime heating without rapid intensification. A low-to-moderate chance of showers or drizzle (10–30% probability in several runs) introduces slight downside risk to the peak, helping explain the secondary weight on 27°C. Early September climatology for the region shows typical maxima of 27–29°C as the East Asian monsoon wanes and high-pressure influences strengthen, providing a stable baseline that aligns with current model consensus. No major synoptic shifts—such as a strong cold front or heat dome—are indicated in the 24–48 hour window, keeping probabilities anchored near the historical norm with limited tail risk for extremes above 30°C or below 26°C. Updated model runs and official briefings closer to the date will be the key near-term catalysts for any probability shifts.