**Trader sentiment for Seoul's August 2026 precipitation reflects substantial uncertainty around typical late-summer variability, with market-implied probabilities clustered near 44–46.5% across bins from under 150 mm to over 500 mm.** August climatology shows an average of roughly 350 mm driven by the tail end of the East Asian summer monsoon and occasional typhoon influences, after the main rainy season typically withdraws by late July per Korea Meteorological Administration patterns. Current conditions feature persistent heat and limited immediate rainfall, yet differentiation among outcomes hinges on steering patterns, moisture convergence, and any northward typhoon tracks that could deliver episodic heavy totals. Model consensus remains limited this far ahead, with traders weighing the balance between drier post-monsoon subsidence and potential convective bursts or tropical remnants that historically swing monthly accumulations by 100–200 mm.