Trader consensus in the Busan highest-temperature market centers on 24–25°C implied probabilities near 42% and 41%, reflecting model agreement on a moderating cold-air advection from a strengthening continental high over northern China. This northerly flow, expected to lower surface temperatures by several degrees after October 1, is offset by clear to mostly sunny conditions that promote strong daytime radiative heating and weak sea-breeze moderation along the southern coast. Ensemble guidance shows limited spread in maximum temperatures, with differences hinging on exact wind speeds and boundary-layer mixing; historical early-October averages near 22°C provide context for the elevated market-implied range. Fresh Korea Meteorological Administration runs and updated high-resolution forecasts arriving within the next 24 hours represent the key data points that could shift the narrow 24–25°C contest.