April 9, 2026 - April 10, 2026: The prices of multiple options at or below 27°C plummeted (e.g., 27°C dropped from 28.5c to 2.25c, and 26°C from 24c to 2c). This was driven by the updated 9-day forecast from the Hong Kong Observatory, which confirmed a significant temperature rise to around 30°C due to a southerly airstream. Meanwhile, the '31°C or higher' option fluctuated heavily between 16.5c and 29c as the market continuously reassessed the likelihood of extreme daytime heating breaking the 31°C threshold.

April 10, 2026 - April 10, 2026, the price of '23°C or higher' plunged from 56.5c to 27c, as updated meteorological models ruled out extreme heat scenarios, shifting the consensus slightly lower. April 9, 2026 - April 10, 2026, the price of '22°C' climbed from 18.5c to 31.5c, because the downward revision in heat expectations made 22°C one of the most probable peak targets. April 9, 2026 - April 10, 2026, the price of '21°C' steadily rose from 16.5c to 27c, also driven by the correction of the upper temperature bound and increasing short-term forecast certainty.

Betting on the specific highest temperature of a city on a given day is a somewhat common niche in prediction markets, but it remains an obscure and unconventional topic for the general public.

April 9, 2026 - April 10, 2026, the price of '20°C or higher' plummeted from 72.5c to 33.5c, as weather forecasting models revised the expected high temperatures for April 13 downwards. April 9, 2026 - April 10, 2026, the price of '18°C' surged from 9c to a peak of 28.5c before settling at 24.5c, driven by the cooler forecasts making 18°C a highly probable outcome. April 9, 2026 - April 10, 2026, the price of '19°C' increased from 10c to 24c, also reflecting the downward shift in temperature predictions.

Although the market has significantly reduced the odds for 20°C or higher, it still holds an implied probability of over 30%. However, some mainstream public weather forecasts (such as Google's 10-day forecast) suggest the high on April 13 might only reach 16°C-17°C [2]. This divergence likely stems from discrepancies between different meteorological models (e.g., GFS/ECMWF vs. localized forecasts) or traders betting on rapid, short-lived springtime warming effects in Shanghai.

Predicting the exact daily high temperature of a specific city is a typical weather prediction market. While not uncommon in specialized betting circles, it remains a relatively niche topic that the general public and non-locals would not ordinarily think about.

From April 9, 2026 to April 10, 2026, the price of '11°C or higher' surged from 59.5c to 98c, while '10°C' plummeted from 30c to 1.4c, and '9°C' dropped from 16.5c to 0.6c. This was caused by the convergence of short-term weather models as the date approached, definitively ruling out a late spring cold snap and confirming the high will easily exceed 11°C. There are no prior records of price spikes exceeding 10c. The overall market pricing had remained relatively stable, adjusting slightly according to daily rolling weather forecast updates.

Although weather forecasting is part of daily life, placing precise bets on the highest temperature of a specific city on a given day is relatively niche among the general public, making it a moderately novel prediction market topic.

April 9, 2026 - April 10, 2026, the Yes price for '20°C' fluctuated, dropping from 30.5c (Apr 9, 22:23) to 11.0c (Apr 10, 12:28) before recovering to 26.5c (Apr 10, 18:58). This was due to volatility in weather forecast models regarding whether the high would reach 20°C. April 9, 2026 - April 10, 2026, the Yes price for '21°C' dropped from 23.0c (Apr 9, 16:58) to 4.0c (Apr 10, 18:58), as the likelihood of temperatures reaching 21°C decreased significantly as the date approached. April 9, 2026 - April 10, 2026, the Yes price for '22°C or higher' plummeted from 30.5c (Apr 9, 08:18) to 3.5c (Apr 10, 18:58), because extreme high-temperature forecasts were revised downwards, making 22°C highly unlikely. April 9, 2026 - April 10, 2026, the Yes price for '18°C' rose from 12.0c (Apr 9, 08:18) to 27.0c (Apr 10, 18:58), as downward revisions in temperature forecasts made 18°C a more probable high.