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 4 Jun '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 until data for this date has been published. The resolution source for this market measures temperatures in Celsius to one decimal place (eg, 9.1°C). Thus, this is the level of precision that will be used when resolving the market.
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 or below | 0% YES | 100% NO |
| 23°C | 0% YES | 100% NO |
| 24°C | 1% YES | 100% NO |
| 25°C | 1% YES | 99% NO |
| 26°C | 1% YES | 99% NO |
| 27°C | 9% YES | 92% NO |
| 28°C | 36% YES | 65% NO |
| 29°C | 56% YES | 45% NO |
On 4 June 2026, the Hong Kong Observatory will record the lowest temperature for that day in degrees Celsius. This market resolves based on the absolute daily minimum temperature published in the Observatory's Daily Extract, measured to one decimal place. The settlement window closes at midday UTC on 4 June, after which the Observatory typically publishes finalised data within days.
Hong Kong's June temperatures are shaped by the onset of the southwest monsoon and pre-summer heat. Historical June minima typically range between 24–26°C, with the Observatory's 30-year climate normal for June averaging around 25.5°C. Extreme lows below 23°C are rare in June, occurring perhaps once per decade when unusual weather systems pass through. The current 0% implied probability on Polymarket's order book suggests traders are pricing in minimal likelihood of exceptionally cold conditions, reflecting seasonal norms. This probability formation reflects the typical meteorological pattern rather than any specific forecast signal.
Traders should monitor the extended-range forecasts from the Hong Kong Observatory and regional meteorological agencies as early June approaches. Tropical cyclone activity in the western Pacific, whilst uncommon in early June, represents the primary catalyst for anomalous cooling. The Observatory publishes 9-day forecasts and monthly outlooks that would signal any unusual pressure systems or wind patterns. Sea surface temperatures in the South China Sea, typically 28–29°C in early June, influence local minima; any deviation would warrant reassessment of the probability distribution across temperature bands.
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 June 4?" 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 $19K of resting liquidity puts this market in the below the median by volume for weather contracts on PolyGram. Order-book depth is modest — expect a couple of cents of slippage on $1k+ trades.
Last 24 hours alone saw $3K 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 4 June 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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