Highest temperature in Hong Kong on August 15?

Platform comparison

Market context

On 15 August 2026, the Hong Kong Observatory will record the day's maximum temperature in degrees Celsius. That single data point—published to one decimal place in the Observatory's Daily Extract—determines which temperature band this contract settles into. Polymarket currently prices all outcomes at zero, reflecting the market's inability to assess an event nearly two years distant with meaningful conviction. USDC collateral on Polygon sits idle until the settlement window closes on 15 August at 12:00 UTC, at which point the Hong Kong Observatory's official reading becomes binding.

Historical August temperatures in Hong Kong cluster tightly around 32–33°C for daily maxima, with extreme heat occasionally pushing toward 35°C during particularly intense heat waves. The Observatory's records from the past decade show that August 15 specifically has tracked between 31.5°C and 34.2°C, placing it within the typical late-summer range rather than at the month's statistical extremes. This historical band provides the baseline against which traders should calibrate their conditional token positions.

Traders monitoring this contract should track the El Niño Southern Oscillation (ENSO) phase and the Northwest Pacific typhoon season intensity as they develop through 2025 and early 2026. The Hong Kong Observatory publishes seasonal outlooks each quarter; its February 2026 forecast will offer the first substantive signal for August conditions. Tropical cyclone activity in the weeks preceding mid-August could suppress temperatures through cloud cover and rainfall, whilst a high-pressure system would elevate them. The Observatory's data publication typically occurs within 48 hours of the observation date, allowing settlement to proceed promptly after 15 August.

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 Kalshi UK, 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 Kalshi 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%.