Highest temperature in Beijing on August 21?

Platform comparison

Market context

Beijing's peak temperature on 21 August 2026 will be measured at the Capital International Airport Station and recorded in Weather Underground's Daily Observations table, with settlement determined by whichever temperature band contains that highest reading in degrees Celsius. The market currently prices this contract at 0% YES across all temperature ranges, suggesting traders view the event as either already determined or requiring significant new information before meaningful positions emerge. On Polygon, USDC holders can stake conditional tokens against specific temperature brackets, with payouts distributed only to those holding the correct range at settlement on 21 August at 12:00 UTC.

Historical August temperatures at Beijing Capital Airport show a consistent pattern: daily highs typically range between 26–32°C during this period, with occasional peaks above 33°C during heat waves. The 30-year average high for mid-August sits around 29°C, though the city has recorded extremes of 40°C+ during exceptional heatwaves in recent decades. Current probability clustering near zero suggests the market may be awaiting baseline forecasts or treating this as a placeholder contract until seasonal weather models become more reliable.

Traders should monitor China Meteorological Administration updates and any heat advisories issued in early August 2026, as these typically precede significant temperature deviations. Beijing's urban heat island effect and proximity to the Yangtze River basin influence summer patterns; any unusual atmospheric pressure systems or monsoon activity reported by regional weather services would shift implied probabilities toward higher temperature ranges. Settlement hinges entirely on Weather Underground's Daily Observations feed, making data source verification critical before position entry.

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 PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 PolyGram. 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%.