Between April 6, 2026, and April 8, 2026, the price of '15°C' plummeted from 31c to 0.4c as expectations for a warm day completely dissipated. Between April 6, 2026, and April 8, 2026, the price of '14°C' dropped from 26.5c to 0.4c for the same reason. Between April 6, 2026, and April 8, 2026, the price of '13°C' crashed from 29.5c to 0.6c, mainly due to a significant downgrade in the expected temperature for April 10 in the weather forecasts. Between April 6, 2026, and April 8, 2026, the price of '6°C or below' surged from 8c to a high of 43.4c, before settling around 32.2c, driven by an incoming cold front that lowered the expected maximum temperature to 6°C or lower. Between April 6, 2026, and April 8, 2026, the prices of '7°C' and '8°C' also climbed from low single digits to around 30c and 25c respectively, reflecting the confirmation of the cooling trend.

The title states 'Seoul', but the resolution criteria explicitly use data from the Incheon Intl Airport station (RKSI). Incheon airport is coastal and often records different temperatures than downtown Seoul, creating a significant title-rule discrepancy trap. Furthermore, it strictly relies on Wunderground's whole-degree Celsius data and ignores any post-finalization revisions.

Between April 8, 2026, and April 9, 2026, the price of '11°C' surged from 16c to 27c, while '14°C' plummeted from 20.5c to 9.5c. This is because, as the resolution date nears, updated meteorological forecasts indicated a higher probability of the peak temperature landing in the lower 11-13°C range, drastically reducing the odds of higher temperatures. Between April 6, 2026, and April 7, 2026, the price of '17°C or higher' plummeted from 30c to 13c, as weather forecasts became clearer closer to the date, reducing the likelihood of unusually high temperatures. Between April 6, 2026, and April 7, 2026, the price of '12°C' surged from 10.5c to 22c, driven by updated meteorological data indicating a much higher probability of the daily high falling in this range. Between April 6, 2026, and April 7, 2026, the price of '13°C' dropped from 26.5c to 16.5c before rebounding to 21.5c, reflecting fluctuations in forecast models across adjacent temperature bins.

While weather derivatives exist in traditional finance, betting on the exact daily high temperature of a specific city is still a somewhat niche and novelty topic for retail prediction markets.

April 6, 2026 - April 9, 2026, the price of 23°C steadily surged from 18.5c to 33c. The reason is that as the resolution date approaches, weather forecasting models have become more precise regarding the specific cooling range and precipitation on April 10, solidifying 23°C as the most likely high temperature. April 6, 2026 - April 7, 2026, the price of 23°C surged from 18.5c to 29c as short-term weather forecasts confirmed incoming rain and a cooling trend for April 10, highly favoring this moderate temperature range. April 6, 2026 - April 7, 2026, the price of 28°C plummeted from 13.5c to 2.4c, as approaching precipitation and cloud cover effectively ruled out the possibility of an anomalous heatwave.

April 6, 2026 - April 8, 2026, the price of the '18°C or below' option surged from 40.5c to around 96.5c, as approaching weather forecasts increasingly confirmed that the maximum temperature would be between 14°C and 16°C, well below 18°C. April 6, 2026 - April 8, 2026, prices for most options '19°C' and above plummeted (e.g., '19°C' dropped from 22.5c to 1.25c, '20°C' from 18.5c to 1.1c) because weather forecasts eliminated the possibility of higher temperatures.