Highest temperature in Hong Kong on August 13?

Platform comparison

Market context

On 13 August 2026, the Hong Kong Observatory will record the day's highest temperature in Celsius. Polymarket currently prices this contract at 0% YES, meaning traders are assigning negligible probability to any single temperature band resolving true—a reflection of the settlement window closing at midday UTC on that date, before final Observatory data typically publishes. The contract settles on the "Absolute Daily Max" figure from the Observatory's Daily Extract, measured to one decimal place, once the official record is released.

Hong Kong's August temperatures are remarkably consistent. Historical data from the Observatory shows daily maxima in mid-August cluster tightly between 31°C and 34°C, with extreme outliers rare. The city's subtropical maritime climate, moderated by sea breezes and typhoon season dynamics, produces little variance across years. August 2023 saw daily highs of 32–33°C; August 2024 remained in similar bounds. This stability explains why the crowd has not concentrated probability into any single range—the outcome is genuinely uncertain across a narrow band rather than skewed toward outliers.

Traders monitoring this contract should track the Hong Kong Observatory's seasonal forecasts and any tropical cyclone activity in the Western Pacific during early August 2026. Typhoons can suppress temperatures significantly, whilst high-pressure systems drive them upward. The Observatory publishes extended outlooks roughly two weeks ahead; these will be the primary catalyst for probability shifts. Settlement hinges on the Observatory releasing its Daily Extract for 13 August, typically available within 48 hours of the observation date, making this a straightforward resolution once data becomes available.

Methodology

We track Highest temperature in Hong Kong on August 13? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

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%.