Highest temperature in Hong Kong on July 17?

Platform comparison

Market context

Hong Kong’s highest temperature on 17 July 2026 will be recorded by the Hong Kong Observatory and resolved in degrees Celsius to one decimal place, with the market currently pricing a YES outcome at 0% on Polymarket. Traders on Polygon are locking USDC into conditional tokens tied to specific temperature ranges, betting against the event that the day’s peak heat will fall within the selected bracket once the Daily Extract is finalized.

Historically, mid-July in Hong Kong sees daily maximums typically between 31°C and 34°C, with extreme outliers rarely exceeding 35°C. The Observatory’s climate records show that 17 July has not produced a record-breaking high in recent decades, and the 0% implied probability reflects this stability rather than a sudden cold snap. Comparable cases from 2023 and 2024 confirm that July highs cluster tightly, making wide deviations unlikely without a documented heatwave catalyst.

Traders should monitor the Hong Kong Observatory’s daily weather bulletins and the scheduled release of the Daily Extract, which finalises the “Absolute Daily Max” value. A recent update from the Observatory confirms that data for July 2026 will be published within 48 hours after the date, per standard protocol [1]. No official heatwave announcements have been issued for mid-July 2026, and regional forecasts from the China Meteorological Administration show no extreme temperature anomalies expected in the Pearl River Delta this week.

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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.

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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.