Trader sentiment for Seoul's August precipitation shows a near-even split favoring extremes under 150 mm or 500 mm+, reflecting high uncertainty at the month's start amid lingering East Asian monsoon influences and potential typhoon tracks. Early August forecasts from the Korea Meteorological Administration indicate low precipitation probabilities and heat-wave conditions, consistent with historical tapering after July peaks, yet model consensus on steering patterns and tropical cyclone formation remains divergent. Historical averages near 300 mm can shift sharply with one or two landfalling systems, creating the observed bimodal odds as traders weigh official seasonal outlooks against variability in atmospheric circulation. Updated medium-range and typhoon monitoring from KMA will provide key data points in coming weeks.