**Trader sentiment for Seoul's August 2026 total precipitation reflects the interplay between observed rainfall through late August and short-range forecast uncertainty for the final week.** With the month nearly complete, cumulative totals to date place the outcome near the boundary between lower bins (<150 mm to 200 mm), while ensemble forecasts add roughly 40–50 mm more, primarily from scattered showers and one heavier event around August 30. Official Korea Meteorological Administration guidance indicates mostly light, localized convective activity rather than organized monsoon or typhoon systems, keeping additional accumulation modest but variable. Model spread in timing and intensity of the late-month rain—coupled with typical August climatological variability of 200–300 mm—explains the tight clustering of probabilities around 42–46% across the 150–300 mm range and lower odds for extremes above 350 mm. New daily observations and updated model runs through month-end will sharpen resolution criteria.