Highest temperature in Shanghai on August 17?

Platform comparison

Market context

On 17 August 2026, Shanghai will record a daily high temperature at Pudong International Airport Station. This market invites traders to predict which temperature range will contain that peak reading, measured in degrees Celsius. A YES share pays out if the actual high falls within your chosen range; a NO share pays out if it falls outside. The settlement hinges on Weather Underground's Daily Observations table rather than its summary display—a distinction that matters when automated systems and manual readings occasionally diverge.

Shanghai's August climate is remarkably consistent. Historical data from the past two decades shows daily highs in mid-August cluster tightly between 32 and 35 degrees Celsius, with extremes rarely exceeding 36 degrees or dropping below 31 degrees. The 0% crowd probability currently assigned suggests traders expect an outcome outside typical August bounds, though the market's structure accommodates all plausible ranges. August 2025 saw Shanghai record 34.2 degrees on the 17th; the year prior registered 33.8 degrees on the same date.

Traders should monitor tropical cyclone forecasts issued by the China Meteorological Administration in early August, as these systems occasionally suppress temperatures below seasonal norms. El Niño and La Niña patterns influence broader East Asian weather trajectories, though their August effects on Shanghai are typically modest. Urban heat island effects at Pudong—driven by airport operations and surrounding development—tend to elevate readings relative to rural stations. The settlement window closes at noon UTC on 17 August, allowing only morning observations to influence final resolution.

Methodology

We track Highest temperature in Shanghai on August 17? 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

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 Prediction Market 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%.