April 22, 2026 - April 23, 2026, the price of the 19°C option plummeted from 38.5c to 19c (before recovering slightly to 24c), as updated granular weather models ruled out extreme warming scenarios, slightly lowering the expected peak temperature. April 22, 2026 - April 23, 2026, the price of the 18°C option surged from 34c to 46.5c, driven by a growing consensus among major meteorological forecasts (predicting a high of 64°F/18°C), making it the most probable target range for the daily high.

April 22, 2026 - April 24, 2026, the prices of the 21°C, 22°C, and 23°C options plummeted from over 30c to less than 1c, while the prices of the 19°C and 20°C options surged from around 15c to approximately 47c. The 18°C option also briefly spiked to 38c before pulling back. The reason is a strong cold front sweeping across Hong Kong causing a drastic drop in temperature, prompting the Observatory to revise its minimum temperature forecast down to around 19 degrees.

Between April 22, 2026, and April 24, 2026, the price of 68-69°F surged from 3.5c to 29c, due to updated weather forecasts adjusting the expected low temperature downwards. Between April 22, 2026, and April 24, 2026, the price of 66-67°F plummeted from 30c to 4.5c, as the likelihood of temperatures dropping into this range was ruled out by newer meteorological models closer to the date.

This is a typical weather prediction market. While weather derivatives are common in professional trading, the general public rarely predicts and monitors the exact lowest temperature of a specific city on a given day in their daily lives, giving it a somewhat niche and novelty appeal.

Between April 22, 2026 and April 24, 2026, the price of the 12°C option surged from 19.5c to 95.5c, as the weather forecast became highly certain with the approaching date, locking in 12°C as the most probable lowest temperature. Between April 22, 2026 and April 24, 2026, the price of the 11°C option plummeted to 3.5c after reaching a peak of 29c, as updated forecasts indicated the temperature is very unlikely to drop to 11°C. Between April 22, 2026 and April 24, 2026, the price of the 10°C option fell from a high of 25c to 0.25c, as the possibility of temperatures falling below 11°C was entirely ruled out as the actual date arrived.

April 22, 2026 - April 24, 2026, the price of the 14°C option surged from 16.5c to 52.5c, while the prices for 11°C and 12°C dropped significantly. This shift was driven by real-time meteorological data for Tokyo on April 24, which indicated a warmer morning than previously forecasted.