Highest temperature in Hong Kong on August 18?

Platform comparison

Market context

Hong Kong's peak temperature on 18 August 2026 will be measured by the Observatory's official daily maximum reading, with settlement contingent on data publication in their Daily Extract records. The 0% crowd probability reflects the market's nascent stage rather than any meteorological certainty; August temperatures in Hong Kong routinely exceed 32°C, with historical August maxima frequently reaching 34–36°C depending on monsoon patterns and tropical cyclone activity.

August represents Hong Kong's hottest month climatologically, sitting at the tail end of the southwest monsoon season. Historical records show considerable variability: the territory has recorded August daily maxima ranging from approximately 30°C in cooler years to 37°C during heat waves. The 2023 August period saw multiple days exceeding 34°C, whilst 2022 experienced more moderate peaks around 32–33°C. This variance underscores how seasonal weather patterns, upper-level atmospheric circulation, and proximity to tropical systems drive outcomes across the month's final stretch.

Traders should monitor meteorological forecasts issued in mid-August 2026, particularly from the Hong Kong Observatory's extended outlooks and any tropical cyclone warnings that could suppress temperatures through increased cloud cover and rainfall. The settlement window closes at 12:00 UTC on 18 August, after which the Observatory's official recording becomes the binding reference. Data publication typically occurs within days of the observation date, though traders cannot settle positions until the Daily Extract is formally released and verified.

Methodology

This page reviews Highest temperature in Hong Kong on August 18? 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 Prediction Today, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Prediction Today. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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%.