With roughly half of June 2026 elapsed and only modest early-month showers recorded, Seoul’s running precipitation total sits well below the long-term climatological average of 130–144 mm. This positions the 120–130 mm bin as the market leader at 37.5 % implied probability, ahead of nearby ranges. The Korea Meteorological Administration outlook and ensemble guidance indicate the East Asian monsoon (Jangma) will likely strengthen after mid-June, raising the chance of heavier late-month rainfall that could push totals toward 140–160 mm or higher; however, model spread in onset timing and intensity keeps the distribution relatively flat across the central bins. Traders therefore balance the drier first-half baseline against the uncertain monsoon contribution still to come.