The title asks for the lowest temperature in Seoul, but the resolution rules explicitly state that data from Incheon International Airport (RKSI) will be used. Incheon Airport is located on an island, and its microclimate can differ significantly from central Seoul. This is a major trap for traders relying solely on Seoul weather forecasts.

From May 12 to May 14, 2026, the price of 16°C surged from 15.5c to a peak of 32.5c before settling at 25.5c. This volatility was caused by forecast models adjusting and converging their nighttime temperature predictions as the resolution date approaches. From May 12 to May 14, 2026, the price of 14°C plummeted from a high of 31.5c down to 9c, as the latest forecasts ruled out the possibility of temperatures dropping that low. Between 09:58 and 12:08 on May 12, 2026, the price of 13°C surged from 8.5c to 20.5c. This was driven by short-term weather forecast updates, where models increased the expected impact of cold air, prompting the market to reprice the probability of lower temperatures. Between 03:28 and 07:48 on May 12, 2026, prices for 12°C and 11°C or below dropped significantly, reflecting the market ruling out extreme low temperatures as the date approaches.