Highest temperature in Hong Kong on August 11?

Platform comparison

Market context

Hong Kong’s maximum temperature on 11 August will be set by the Hong Kong Observatory’s “Absolute Daily Max (deg. C)” for the day, published later in the Daily Extract. For a programmatic trader, the key practical issue is that the market only resolves once that extract is final, so the live price is really a forecast of the Observatory’s end-of-day peak rather than an intraday reading. The current crowd is already clustering around **34°C** and **35°C**, which fits the normal August profile: the Observatory’s 1991–2020 daily normals put 11 August around **31.1°C** for the mean maximum, with warm, humid conditions typical of the season.[3][2]

For calibration, recent precedent matters more than the broad climate average. The Observatory said Hong Kong hit **36.9°C** on 9 August 2026, the city’s hottest day on record, which shows the atmosphere can still produce an extreme spike even late in a hot spell.[6][15] The same source also reported **34.4°C** on 10 August 2025 as the monthly maximum for that August, while the current market page cites model guidance for **34–35°C** on 11 August under persistent southeasterly flow and high boundary-layer moisture.[5][2] In other words, the probability structure is being driven by whether heat is sustained at record-adjacent levels or trimmed back by cloud and showers.

A trader using tooling would watch the Observatory’s hourly readings, short-range forecasts, and any overnight update cycle rather than waiting for the settlement file itself. The official readings page shows how quickly the station network can move from morning to afternoon heat, and the forecast pages indicate whether showers or cloud are likely to cap the day’s high.[12][14] Time-and-date’s Hong Kong outlook for 11 August also points to a hot day with possible early showers and a high in the mid-30s Celsius, which is consistent with the market’s top outcomes and helps explain why copy-trading or conditional orders would likely key off revisions in the forecast rather than a single headline temperature.[9]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on August 11? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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.

UK Frequently Asked Questions

Where can I trade this market with the lowest fees?

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

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Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.