2026-04-06 - 2026-04-07, The price of the 21°C option plunged from 19.5c to 5.5c, and 20°C fell from 35c to 26.5c. This occurred because, nearing settlement, the latest weather forecasts largely ruled out temperatures exceeding 20°C, causing expectations to converge further toward 18-19°C. 2026-04-04 - 2026-04-06, The price of the 19°C option climbed steadily from 15.5c to 40c, while the 21°C option fell from 19.5c to 10c. This was caused by the convergence of weather models as the date approached, locking the expected peak temperature around 19°C and leading capital to concentrate on the most likely range. 2026-04-04 - 2026-04-06, The price of the 21°C option climbed rapidly from 4.5c to 19.5c, and the 20°C option rebounded from a low of 12.5c to 32c. This upward shift was driven by updated meteorological models slightly raising the expected peak temperature as the date approached. 2026-04-03 - 2026-04-04, The price of 19°C surged from 15.5c to 36c, 20°C dropped from 28c to 17.5c, 16°C or below spiked to 27c then fell to 4.5c, 21°C fell from 17.5c to 6c, and 22°C plunged from 11.5c to 1.5c before settling at 4.5c. This high volatility was driven by updated weather forecasts confirming a peak temperature of 18-19°C on April 7, ruling out earlier possibilities of extreme cold and highs above 20°C.

April 5, 2026 - April 6, 2026: The price of 'Choosin' Texas - Ella Langley' further increased from 84c to approximately 98c, as continuous updates of this week's streaming data made the song's lead unshakeable, leading to full market consensus. April 4, 2026 - April 5, 2026: The price of 'Choosin' Texas - Ella Langley' surged from 35c to 84c, while almost all other tracks, including Babydoll, American Girls, and Porch Light, experienced drastic drops of 20c to 40c. The reason is the release of weekend daily Spotify streaming data, which clearly established 'Choosin' Texas' as the undisputed leader, causing capital to consolidate and correcting early market pricing chaos.

April 6, 2026 - April 7, 2026, the price of the 24°C option surged from 13c to 45c (later settling around 34.5c), and the 25°C option surged from 4.2c to 17.7c; concurrently, the 22°C option plummeted from 32.5c to 8.5c. This occurred because updated meteorological models significantly raised the expected high temperature, prompting traders to shift their consensus rapidly from the 22-23°C range up to the 23-24°C or even 25°C range. April 4, 2026 - April 5, 2026, the price of the 22°C option surged from 12.5c to 31.5c, and the 23°C option surged from 13c to 28.5c, while the 24°C option plummeted from 27c to 13c. This shift occurred as early meteorological models slightly downgraded the expected high temperature, shifting trader consensus from 24°C down to the 22°C-23°C range.

There is a notable divergence. Mainstream weather forecasts (e.g., Google Weather/Weather.com) currently predict a high of 72°F (approx. 22.2°C) for Paris on April 8. However, Polymarket traders are heavily favoring 23°C and 24°C, which together account for over 60% of the implied probability. This discrepancy likely arises because traders are factoring in the specific historical measurement biases at the Wunderground CDG station, or they are anticipating a faster progression of the unusually warm air mass currently moving across Western Europe, thus pricing in a premium over generic forecasts.

From April 6, 2026, to April 7, 2026, the price of '24°C or higher' surged from around 41.5c to 64.5c as weather models further confirmed unseasonably extreme heat in London. From April 6, 2026, to April 7, 2026, the price of '22°C' plummeted from 30c to approximately 6.5c, because expectations for high temperatures were upgraded, ruling out milder conditions. From April 6, 2026, to April 7, 2026, the price of '24°C or higher' fell from 68c to 50.5c (before rebounding), likely because weather forecast models slightly revised their extreme predictions downwards as the date drew nearer. From April 5, 2026, to April 6, 2026, the price of '24°C or higher' surged from around 6.5c to 68c, as the latest short-term weather models sharply upgraded the forecast for extreme high temperatures in the London area. From April 5, 2026, to April 6, 2026, the price of '21°C' plummeted from around 29.5c to 8c, due to the market's reduced expectation for milder temperatures. From April 4, 2026, to April 5, 2026, the price of '22°C' increased from around 21c to approximately 27.5c, peaking at 33.5c, as short-term weather models concentrated the expected temperature in this range. From April 4, 2026, to April 5, 2026, the price of '19°C' dropped from around 17.5c (peak 24.5c) to about 5.5c, due to revisions in the forecast reducing the likelihood of unusually low temperatures as the date approached. From April 4, 2026, to April 5, 2026, the price of '24°C or higher' fell from around 14c to about 6.5c, reflecting a decreased probability of extreme high temperatures (before sharply rebounding).

There is a potential ambiguity in the rules: it mentions using the highest temperature recorded by the 'Forecast', but provides a link to the 'history' (daily observations) page. Additionally, the outcome is strictly bound to the Charles de Gaulle Airport (LFPG) station data and rounded to whole degrees Celsius, which might slightly deviate from downtown Paris data or other weather sources.

From 2026-04-06 to 2026-04-07, the price of the 23°C option dropped from 45.5c to 32.5c, and the 22°C option fell from 31.5c to 21.5c, while the 24°C option rose from 15c to 24.5c. This reflects updated morning forecasts leaning towards slightly higher-than-expected afternoon temperatures. From 2026-04-05 to 2026-04-06, the price of the 22°C option dropped from 43.5c to 22.5c, while the 23°C option surged from 31c to 45.5c, as updated forecasts near expiration increasingly favored a peak of 23°C. From 2026-04-03 to 2026-04-06, the price of the 21°C option plummeted from 24c to 3.2c, as current meteorological models effectively ruled out lower temperature possibilities. From 2026-04-03 to 2026-04-04, the price of the 24°C option fell from 25.5c to 10c before slightly recovering, reflecting market repricing of the likelihood of slightly higher temperatures.