Recent clearing after widespread rain on September 25–26 has left Busan under mostly cloudy to partly cloudy skies on the 27th, with light southerly winds and weak pressure gradients limiting strong advection. Korea Meteorological Administration guidance and ensemble model runs point to daytime highs of 25–28°C, with the tight 27–28°C market split reflecting uncertainty in cloud cover timing, residual boundary-layer moisture, and exact insolation. Historical late-September maxima average near 24–26°C, but recent warmer anomalies and southerly flow have nudged trader-implied odds toward the upper end of the typical range. Updated KMA briefings and next model cycles will refine the peak reading ahead of resolution.