**Trader sentiment for the lowest temperature in Seoul (Incheon) on August 4, 2026, centers on 27°C as the modal outcome (50.5% implied probability), followed by 28°C (26.5%) and 26°C (10.5%).** This distribution reflects short-range model consensus from the Korea Meteorological Administration (KMA) and other sources showing overnight lows of 26–28°C under a stable high-pressure regime with clear to mostly clear skies and high humidity limiting radiative cooling. Primary scientific drivers include typical mid-summer conditions: elevated sea-surface temperatures sustaining warm, moist air masses, light winds reducing mixing, and urban heat effects around Incheon that moderate minimums near the seasonal average low of ~23–25°C but push realized values higher amid the current heatwave pattern. Recent KMA short-term guidance explicitly forecasts a 26°C minimum for August 4 with low precipitation probability, while broader outlooks for early August note daytime highs of 34–37°C and overnight lows in the 25–27°C range, with limited model spread expected until closer to the date. Upcoming KMA updates and refined numerical weather prediction runs over the next 48 hours will likely determine whether probabilities shift toward 26°C or remain anchored near 27–28°C.