Lowest temperature in Hong Kong on August 5?

Platform comparison

Market context

Polymarket currently prices this Hong Kong minimum-temperature contract with **27°C** as the leading outcome at about **45–46%**, while **26°C** is the next most likely reading at roughly **29%** and the lower buckets sit much further back.[1] That means traders are effectively treating a sub-26°C print at the Observatory as a low-probability tail event, even though the market settles on the Hong Kong Observatory’s published *Absolute Daily Min* for 5 August in Celsius to one decimal place.[1][6]

That distribution is consistent with Hong Kong’s August climate, when overnight lows are usually in the high 20s and humidity keeps the floor elevated.[2][4] A useful comparator is August 2025, when the Observatory’s monthly write-up recorded a daily minimum of **24.0°C** on 5 August amid heavy rain, showing that sharp rain-cooled dips can happen, but they are weather-system dependent rather than the norm.[16] The contract’s on-chain mechanics also matter: positions are bought with **USDC** on **Polygon**, and the winning conditional token redeems at **$1** once the market resolves.[1]

The main catalysts are the Observatory’s forecast updates, the actual overnight weather on 5 August, and the timing of the final Daily Extract publication, because the market cannot resolve until that file is posted and later revisions are excluded.[1][6] In practice, traders should watch the HKO regional forecast pages and official city weather bulletins for signs of monsoon troughs, thunderstorms, or rain bands that could suppress the minimum temperature.[3][9] A late-night shower can matter more here than the daytime high, because the contract is keyed to the coldest reading reached before the settlement cut-off.[1]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

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.

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 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.

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%.