Highest temperature in Hong Kong on August 19?

Platform comparison

Market context

On 19 August 2026, the Hong Kong Observatory will record the day's maximum temperature in degrees Celsius to one decimal place. That single reading will determine which temperature band resolves YES on Polymarket. Currently, the market shows 0% implied probability across all outcome ranges, reflecting either sparse liquidity or a technical lag in pricing—a common state for weather contracts far from settlement. Once traders begin depositing USDC on Polygon and minting conditional tokens, price discovery will accelerate and one or more bands will show non-zero probability.

Hong Kong's August temperatures are remarkably consistent. The Observatory's historical data shows absolute daily maxima in August cluster tightly between 32°C and 34°C, with readings above 35°C occurring in fewer than 5% of years on record. The city's maritime subtropical climate and urban heat island effects create a narrow band of likely outcomes. Comparing this to mid-August 2023 (33.4°C) and 2024 (33.1°C) provides a useful baseline: extreme heat events pushing above 36°C are rare enough that markets pricing them should reflect genuine scarcity, not routine August conditions.

The key variable is whether tropical cyclone activity or an unusual heat dome develops in the South China Sea during mid-August 2026. The Hong Kong Observatory publishes seasonal forecasts and typhoon alerts on its website; traders should monitor June and July 2026 advisories for any indication of atmospheric patterns that might suppress or elevate temperatures. Settlement depends entirely on the Observatory's published "Daily Extract" data, which typically appears within days of the date in question, though delays are possible during severe weather events.

Methodology

This page reviews Highest temperature in Hong Kong on August 19? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Polymarket Scam?, which mirrors the Polymarket order book at 0% fees.

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 Polymarket Scam?. 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%.