Resolution criteria on PolyGram: This market will resolve to the temperature range that contains the lowest temperature recorded by the Hong Kong Observatory in degrees Celsius on 12 May '26. The resolution source for this market will be information from the Hong Kong Observatory, specifically the "Absolute Daily Min (deg. C)" the specified date once information is finalized in the relevant "Daily Extract", available here: https://www.weather.gov.hk/en/cis/climat.htm This market can not resolve to "Yes" until data for this date has been finalized. The resolution source for this market measures temperatures in Celsius to one decimal place (eg, 9.1°C).
PolyGram is an on-chain prediction market where you trade YES or NO outcome shares with real USDC on Polygon. For this market, buy YES if you believe the event will happen, or NO if you think it won't. Your maximum loss is your stake — winning shares pay $1.00 each at resolution. Unlike sportsbooks, there is no house edge: prices are set by supply and demand from other traders and reflect the crowd's real-time probability.
Market outcomes
| 22°C | 4% YES | 97% NO |
| 23°C | 19% YES | 82% NO |
| 19°C or below | 0% YES | 100% NO |
| 21°C | 0% YES | 100% NO |
| 20°C | 0% YES | 100% NO |
| 24°C | 52% YES | 48% NO |
| 25°C | 29% YES | 71% NO |
| 26°C | 1% YES | 99% NO |
This market resolves based on the lowest temperature recorded by the Hong Kong Observatory on 12 May 2026. The settlement window closes at midday UTC on that date, after which the Observatory's finalised daily extract will determine which temperature range contains the actual minimum. The current order book on Polymarket implies a 4% probability that the lowest temperature falls into whichever range this contract represents, suggesting traders assess it as an unlikely outcome relative to other temperature bands available for that date.
Hong Kong's May climate typically features warm, humid conditions with daily minimums between 23–26°C. Historical data from the Observatory shows that temperatures below 20°C on a May day are exceptionally rare in Hong Kong's subtropical climate, occurring only during unusual weather systems. The 4% implied probability reflects this seasonal baseline; achieving an unusually low minimum would require either an atypical cold front or a significant weather disruption during late spring.
Traders should monitor tropical cyclone forecasts and upper-air pattern developments in the weeks preceding 12 May, as these represent the primary catalysts for anomalous cooling. The Hong Kong Observatory publishes seasonal outlooks and maintains real-time weather alerts; any significant forecast shifts toward cooler conditions in early May could shift the order book substantially. Settlement depends entirely on the Observatory's finalised data publication, which typically occurs within days of the measurement date.
Resolution is handled by the UMA optimistic oracle on Polygon. A proposer submits the outcome, a two-hour dispute window opens, and if no one stakes a counter-claim the payout is final. Contested outcomes escalate to UMA token-holder voting. Payouts clear in USDC to the winning side.
The mechanics for trading "Lowest temperature in Hong Kong on May 12?" are the same as any other PolyGram event contract. Each YES share resolves to $1 if the event happens, or $0 if it doesn't. The current price between 0¢ and 100¢ is the market's probability estimate, set live by the order book.
$3K in lifetime turnover and $8K of resting liquidity puts this market in the below the median by volume for weather contracts on PolyGram. Order-book depth is thin — large orders may need to be split across the book or executed as limit orders.
Last 24 hours alone saw $2K in turnover, well above the lifetime daily-average for this market — a clear sign of news catalysing trader activity right now.
The market has been open for under a month — fresh enough that information asymmetry remains a real factor.
Higher-volume markets tend to have tighter spreads and faster price discovery — meaning the displayed YES/NO percentages are more likely to reflect the true crowd-implied probability rather than a single trader's directional view.
Resolution is handled by the UMA optimistic oracle on Polygon. A proposer submits the outcome, a 2-hour dispute window opens, and if uncontested the payout is final. Contested outcomes escalate to UMA token holders.
This prediction market is scheduled to close on 12 May 2026. After the resolving event occurs, settlement typically clears within 24 hours once the UMA optimistic oracle confirms the outcome. All payouts are in USDC on the Polygon network.
To trade on this prediction market, create a free PolyGram account at polygram.ink, deposit USDC via Polygon, and place a YES or NO order on the outcome you believe in. You can learn more on our how-it-works page. Your maximum loss is limited to your stake — there is no leverage or margin.
When the outcome is determined, winning YES shares pay out $1.00 each in USDC, while losing shares pay $0. Settlement is handled by the UMA optimistic oracle on Polygon — a proposer submits the result, a two-hour dispute window opens, and if uncontested, payouts are distributed automatically. You can withdraw your winnings to any Polygon wallet.
Prediction-market positions can lose 100% of staked capital. Outcomes are uncertain by definition — historical accuracy of crowd-implied probabilities is high in aggregate but not for any single market. PolyGram does not provide investment advice. Trade only with capital you can afford to lose.
Regulatory status varies by jurisdiction. Germany, the United States, and most EU countries treat Polymarket-style event contracts under one of three frameworks: financial derivative, gambling product, or unregulated novel asset. Consult local counsel before trading.
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