Traders see the tight spread between 23–27°C as reflecting model uncertainty in Seoul’s overnight minimum for July 31, driven by variable cloud cover, humidity, and potential monsoon or frontal influences that modulate radiative cooling. Recent ensemble runs from global and regional models show modest disagreement on low-level moisture and wind speed, which can shift the daily minimum by 1–3 °C. With Seoul’s urban heat-island effect and typical July climatology favoring lows near 24–26 °C, the market prices capture both the baseline expectation and the risk of slightly cooler air advection or clearer skies that would allow stronger nocturnal cooling. Updated short-range forecasts and any new precipitation signals over the next 48 hours remain the key catalysts for price movement.