Highest temperature in Hong Kong on July 15?

Platform comparison

Market context

Hong Kong’s highest temperature on 15 July 2026 remains unrecorded, with the Hong Kong Observatory yet to publish its final Daily Extract for that date. On Polymarket, the YES contract for the highest temperature falling in any range is priced at 0% implied probability, reflecting the market’s inability to resolve until official data is finalized. Traders holding conditional tokens on Polygon settle in USDC only once the Observatory releases the “Absolute Daily Max (deg. C)” value, a process that typically occurs within days after the observation date.

Historically, mid-July in Hong Kong sees peak temperatures between 31°C and 35°C, with extreme heat events occasionally pushing above 36°C during humid, stagnant air conditions. The 0% pricing today is not a forecast of cold weather but a mechanical placeholder: the market cannot assign probability to any range until the actual temperature is known. Comparable cases from 2023 and 2024 show similar delays in resolution, with prices converging to 100% for the correct range only after the Daily Extract is published.

The key catalyst is the Hong Kong Observatory’s publication schedule for the Daily Extract, which is not fixed but follows internal data validation protocols. Traders should monitor the Observatory’s climate data portal for the “Daily Extract” release, as no external announcement precedes it. A recent update to the Observatory’s open-data API confirms that CSV files for daily maximum temperatures are now accessible via their official endpoint, reducing latency in data availability but not altering the settlement dependency on the finalized extract [1]. Until that document is issued, the contract remains inert.

Sources: 1

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.