Recent KMA and international model guidance indicates clearing skies after showers on August 21–22 will allow stronger solar heating under the North Pacific high on the 23rd, supporting afternoon highs near 32–33 °C in the Seoul–Incheon area. Key variables creating forecast spread include residual low-level moisture that could sustain scattered clouds or brief showers, urban heat-island effects on official readings, and small timing differences in boundary-layer mixing that shift peak temperatures by 1–2 °C. With the market assigning nearly equal implied probabilities across 28–33 °C, traders are pricing in this genuine short-term uncertainty in maximum temperature rather than a single consensus value. Updated model runs and KMA guidance issued closer to the date remain the primary catalysts likely to shift positioning.