**Forecast models and current atmospheric conditions point to an overnight low near 25–26°C in Busan on August 31, 2026, supporting the closely bunched market-implied probabilities around those levels (25°C at 29%, 26°C at 27%).** Persistent southwest flow is advecting warm, humid maritime air from the East China Sea, with dew points near 24–26°C limiting nocturnal cooling under partly cloudy skies and scattered thunderstorm activity. Multiple short-range guidance runs show minimum temperatures stabilizing in the mid-20s Celsius after daytime highs of 28–30°C, consistent with late-August climatology for the region but slightly above long-term averages due to the absence of a strong frontal passage or enhanced radiative cooling. Key uncertainties differentiating nearby outcomes include timing and coverage of any evening showers—which could enhance or suppress cooling—and minor model spread in boundary-layer moisture. Traders appear to weight the latest model consensus and observed persistence of summer warmth heavily, while assigning lower probability to cooler scenarios (e.g., 22–23°C) absent a clear synoptic driver for greater temperature drops. Resolution will hinge on official Korea Meteorological Administration observations for the calendar day.