Highest temperature in Shanghai on August 11?

Platform comparison

Market context

Shanghai's highest temperature on 11 August 2026 will be measured at Pudong International Airport Station and resolved via the Daily Observations table on Weather Underground, with settlement in USDC upon market close at 12:00 UTC that day. The 0% crowd probability reflects either extreme confidence in a specific temperature range or minimal trading activity; given Shanghai's tropical monsoon climate, August highs typically range between 32–35°C, making any single narrow band a statistical outlier unless the market has fractionalised into multiple competing ranges.

Historical August data from Shanghai shows consistent heat patterns, with daily maxima rarely deviating more than 2–3°C from the seasonal mean. The distinction between Weather Underground's Daily Observations table and the Day High & Low summary matters operationally; discrepancies occasionally arise from station maintenance, sensor recalibration, or reporting lag, which could trigger disputes if the two sources diverge significantly. Traders should cross-reference historical settlement precedents on btc-prediction.bet to understand how such conflicts have been adjudicated previously.

Catalysts include typhoon activity in the Western Pacific—the China Meteorological Administration publishes forecasts weekly—and any anomalous heat domes tracking into East Asia. Funding rates on perpetual weather derivatives, if available, may signal institutional positioning ahead of the resolution window. The settlement mechanism's reliance on a single weather station means localised phenomena (urban heat island effects, temporary sensor issues) carry outsized weight; monitoring Pudong's operational status in early August will be material to final price discovery.

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

UK Frequently Asked Questions

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

Can I use Bitcoin directly?

No, Polymarket operates exclusively in USDC on Polygon. You can bridge BTC to USDC via an exchange or bridge service and deposit on Polygon — typically 10-30 minutes processing time.

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%.