Between 2026-04-10 and 2026-04-11, the price for 14°C surged from 20.5c to 35.5c, while 15°C dropped from 35c to 23c. This was due to updated meteorological models slightly lowering the expected high to the 13-14°C range as the resolution date approaches. Between 2026-04-09 and 2026-04-10, the price for 13°C dropped from a peak of 28c to 11c, reflecting updated weather forecast models shifting away from cooler expectations. Similarly, the 12°C option fell from 20.5c to 2.25c, confirming the initial trend of warming forecasts before the recent adjustment.

The title mentions 'Seoul,' but the rules explicitly state the resolution source is the Incheon Intl Airport Station. Given the geographical distance, temperature differences may occur. Users relying solely on downtown Seoul's weather data might be misled. Additionally, data resolves only to whole degrees Celsius.

April 9, 2026 - April 12, 2026, due to divergent meteorological models regarding the strength of the high-pressure system and the impact of sea breezes on April 13, several core temperature options experienced violent oscillations. Notably, '23°C or higher' surged from ~8.5c to 38.5c on the night of April 9, before plunging back to 4.8c by April 12. Concurrently, '20°C' and '21°C' also saw massive two-way swings of over 15c (e.g., '20°C' dropped from 28c to 10c before bouncing back to 19.5c), as consensus now re-converges to the 19-21°C range.

Betting on the exact daily high temperature of a specific city is a somewhat niche but established category in prediction markets. While routine for locals, forecasting the exact degree is slightly novel for a general audience.

Between 2026-04-10 08:03 and 2026-04-11 11:08, the price of '28°C or higher' plunged from 51c to 34.5c before rebounding, driven by short-term capital games and minor weather model adjustments. Between 2026-04-09 12:33 and 2026-04-09 13:38, the price of '28°C or higher' surged from 28.5c to 42.5c, likely driven by aggressive speculative buying based on short-term weather model fluctuations or misinterpretation of data, causing extreme options to deviate significantly from fundamentals.

The market is severely overestimating the probability of temperatures reaching 27°C and 28°C or higher. Mainstream weather forecasts unanimously predict a high around 25-26°C for April 13, yet the market assigns nearly 70% probability to options of 27°C and above. This is likely due to low liquidity or traders referencing forecasts for incorrect regions (e.g., inland cities).

From 2026-04-09 to 2026-04-11, the Yes price of the 22°C option dropped from 18c to 7.1c, as updated short-term weather forecasts further ruled out the possibility of lower temperatures, shifting the expected center toward 24-25°C. From 2026-04-09 to 2026-04-10, the Yes price of the 26°C option plummeted from a high of 26c to 3.5c (later rebounding slightly to 11.3c on the 11th), because as the forecast date approaches, weather models ruled out the possibility of higher temperatures, shifting the expected high temperature center downwards. From 2026-04-09 to 2026-04-10, the Yes price of the 22°C option dropped from a high of 22c to 6.3c, as forecasts indicated the daily high is unlikely to fall below 23°C, ruling out the cooler range.

From 2026-04-10 06:58:17 to 2026-04-12 07:43:17, the price of the 13°C option plummeted from 30.5c to 12.5c as approaching weather models significantly revised maximum temperature expectations upward, ruling out lower temperatures. From 2026-04-10 04:48:17 to 2026-04-12 06:38:17, the price of the 15°C option surged from 12.5c to 33.5c, as short-term weather forecasts showed a high probability of daytime highs reaching this range. From 2026-04-11 17:38:17 to 2026-04-11 21:58:17, the price of the 16°C or higher option surged from 12c to 26.5c, as updated short-term meteorological data showed a higher potential for peak daytime temperatures. From 2026-04-10 03:43:17 to 2026-04-11 23:03:17, the price of the 12°C option plummeted from 20.5c to 1.65c, as weather models largely ruled out low temperatures with the approaching forecast date. From 2026-04-09 16:53:18 to 2026-04-10 17:48:18, the price of the 14°C option fluctuated from 34.5c to 38.5c, showing an overall upward trend, reflecting increased market confidence in this temperature range.