Highest temperature in Hong Kong on August 7?

Platform comparison

Market context

Polymarket is pricing this Hong Kong Observatory contract at **0% YES** today, so the market is effectively saying the posted outcome is not being assigned any live probability in USDC on Polygon. For settlement, the key number is the Hong Kong Observatory’s final *Absolute Daily Max (deg. C)* for 7 August 2026, and the contract only resolves once that daily extract is published and finalised. On-chain, holders of the relevant conditional tokens are therefore waiting on an external weather print rather than a discretionary judgement call.

The historical frame here is Hong Kong’s late-summer heat profile, which is often already high enough that a single decimal place can matter for range-based markets. The Observatory said the day would be around 34°C in urban areas and a couple of degrees higher in the New Territories, with isolated showers and squally thunderstorms later; it also warned temperatures in parts of the New Territories could reach 36°C or above over the weekend.[5] At 4 a.m., the Observatory had already logged 28°C at its headquarters, with other sites such as King’s Park at 27°C and Wong Chuk Hang at 26°C, underscoring that the day began warm enough to leave room for a higher maximum.[1]

For traders, the practical catalysts are the Observatory’s daytime updates, any shift in rainfall or thunderstorm timing, and the eventual publication of the daily extract that fixes settlement.[5][17][18] The market will not resolve until the final data is posted, so the main dependency is the official Hong Kong Observatory record rather than third-party weather apps or private station readings. In a contract priced at zero, any sustained move in the city’s forecast towards the mid-30s, especially with clear skies before afternoon convection builds, is the sort of input that can matter once the token market starts reflecting the possibility of a hotter final print.[5]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on August 7? 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?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Polymarket Alternative UK. 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.

Is Polymarket legal in the UK?

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%.