Trader sentiment clusters tightly between the 50-70 mm and 70-85 mm bins because Seoul’s October climatology centers near 52 mm, driven by one or two cold frontal passages per week that deliver light, intermittent rain amid otherwise clear, drier conditions. With roughly half the month elapsed and modest accumulations so far, near-term model runs showing 5–20 mm events through mid-month plus variable steering patterns for late-month fronts create genuine uncertainty between near-normal and modestly above-normal totals. Stronger or more frequent systems could push toward the upper bin, while suppressed activity would favor the lower one; updated KMA and ensemble guidance on frontal timing will be the key near-term catalyst.