Lowest temperature in Hong Kong on August 17?

Platform comparison

Market context

Hong Kong's minimum temperature on 17 August 2026 will be determined by the Hong Kong Observatory's official daily reading, with settlement contingent on publication of the "Absolute Daily Min" figure in the Observatory's Daily Extract database. The 0% crowd probability reflects the market's current state rather than any meteorological certainty; August typically sees Hong Kong's daily minima in the 25–27°C range, though variation depends entirely on prevailing weather patterns in late summer.

Historical August data from the Observatory shows daily minimum temperatures rarely fall below 24°C during this month, with the absolute minimum for August across the entire instrumental record standing at 20.5°C (recorded in 1953). More recent decades show August minima clustering between 25–27°C under typical monsoon conditions. The current 0% reading suggests traders are either absent from this particular market or awaiting clearer atmospheric forecasting as the date approaches. August 2026 lies beyond the reliable forecast horizon for meteorological models, meaning probability shifts will likely accelerate significantly in the week preceding the settlement window.

Traders should monitor the Hong Kong Observatory's seasonal outlooks and any tropical cyclone activity in the Western Pacific during early-to-mid August 2026, as storm systems can substantially depress daily minimum temperatures. The Observatory publishes monthly climate summaries and daily weather data consistently; the resolution source is institutional and reliable. Settlement occurs at 12:00 UTC on 17 August, with the Observatory typically releasing daily extrema within 24 hours of observation completion.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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.

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%.