Recent official Korea Meteorological Administration short-range guidance projects a 34°C daytime maximum at Incheon under clear morning skies turning mostly cloudy by afternoon, with negligible precipitation chances. This baseline, set against the broader early-August heatwave that delivered repeated 34°C readings, explains why 32–33°C outcomes dominate trader pricing while 34°C remains plausible. Afternoon cloud cover can reduce incoming solar radiation and limit boundary-layer mixing, differentiating a 31–32°C peak from 33–34°C depending on exact timing and thickness of the deck. Low-level humidity and light easterly flow add modest thermal inertia, yet model consensus on steering patterns keeps extreme outliers below 10% implied probability ahead of the final 48-hour forecast updates.