Trader consensus around mid-June 2026 reflects substantial uncertainty over Seoul's total monthly rainfall, with the 160 mm+ bin leading at 28.5% amid closely grouped probabilities near historical averages of 130–145 mm. The dominant driver is the anticipated onset and intensity of the East Asian monsoon (Jangma), which typically begins in late June and accounts for much of the month's precipitation through persistent southerly flow and frontal systems. Current Korea Meteorological Administration short-range outlooks show only scattered showers so far, but model runs diverge on whether the monsoon arrives early and strengthens or remains delayed and weaker, directly affecting totals in the 100–160 mm range. Additional variables include potential typhoon tracks and sea-surface temperature anomalies influencing moisture transport.