Highest temperature in Shanghai on August 16?

Platform comparison

Market context

Shanghai's peak temperature on 16 August 2026 will be measured at Pudong International Airport Station using Weather Underground's Daily Observations table, the primary resolution source for this contract. The market currently prices this outcome at 0% YES across all temperature bands, reflecting the settlement window's closure date of 12:00 UTC on that day. On Polygon, traders hold conditional USDC positions tied to specific temperature ranges; the winning band resolves to 1.00 and all others to 0.00 once the highest recorded reading is confirmed.

Mid-August temperatures in Shanghai historically cluster between 32–36°C, with occasional peaks above 37°C during heat waves. The city's August average high sits around 32°C, though the 2013 heat wave saw sustained readings above 35°C for extended periods. Weather Underground's Daily Observations table typically records readings at hourly intervals, making it more granular than summary forecasts; this distinction matters for settlement, as the highest single observation—not the day's official high-low range—determines the outcome. Traders should note that tropical systems or stalled high-pressure systems in early-to-mid August can drive temperatures significantly above the seasonal norm.

The China Meteorological Administration releases 10-day forecasts every three days; the final forecast window before 16 August will close around 6 August, providing the most reliable signal for seasonal patterns and any emerging weather systems. El Niño or La Niña conditions in 2026 will influence Pacific typhoon activity and heat dome positioning across East Asia. Real-time monitoring of upper-air patterns and sea-surface temperatures in the Western Pacific becomes critical in the week preceding settlement, as these determine whether Shanghai experiences typical August heat or anomalous conditions.

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 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%.