Highest temperature in Shanghai on August 11?

Platform comparison

Market context

Shanghai will experience peak summer heat on 11 August 2026, with the highest temperature recorded at Pudong International Airport determining the settlement outcome. The market currently prices this event at 0% YES, reflecting the conditional token structure on Polygon where traders hold USDC-backed positions across discrete temperature ranges. Resolution hinges on the Daily Observations table from Weather Underground rather than summary figures, a distinction that matters when intraday readings spike above reported highs.

August represents Shanghai's most intense heat period, with historical data showing daily maxima consistently between 32–36°C during this month. The 2023 summer saw sustained temperatures exceeding 35°C across multiple weeks, whilst 2024 brought comparable patterns with occasional peaks near 37°C. These precedents establish the baseline against which current pricing sits; a 0% probability on any specific range suggests the market has distributed conviction across multiple temperature buckets rather than concentrating on any single outcome.

Traders monitoring this contract should track China Meteorological Administration forecasts released in late July and early August, which typically provide 10-day outlooks with reasonable accuracy for Shanghai's coastal climate. Typhoon activity in the Western Pacific during late summer can suppress temperatures substantially, making tropical cyclone tracking essential context. Recent patterns show that whilst extreme heat remains probable, the precise range settlement depends on atmospheric conditions 18 months forward—a timeframe where seasonal models carry meaningful uncertainty despite Shanghai's predictable summer regime.

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

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.

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%.