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 against Weather Underground's Daily Observations table rather than the Day High & Low summary. The Polymarket contract currently prices this outcome at 0% YES, reflecting either extreme confidence in a specific temperature band or minimal trading activity establishing a floor. Conditional tokens on Polygon settle in USDC, with the market closing to new positions at 12:00 UTC on the resolution date itself—a tight window that rewards traders monitoring real-time meteorological data rather than relying on forecasts issued days prior.

August represents Shanghai's hottest month climatologically, with daily maxima typically ranging between 32–35°C, though extremes have reached 40°C during heat waves. Historical data from the past decade shows that temperatures exceeding 37°C occur roughly once every two to three years during August, whilst readings below 30°C are exceptionally rare. The 0% probability assigned to the current market outcome suggests traders have already positioned heavily into a particular temperature range, leaving minimal liquidity at the extremes.

Weather patterns across East Asia in summer 2026 will depend on the strength and positioning of the Pacific high-pressure system and any tropical cyclone activity in the Western Pacific. The China Meteorological Administration typically issues 10-day forecasts by early August, though these carry substantial uncertainty beyond five days. Traders should monitor typhoon tracks in late July and early August, as systems approaching or skirting Shanghai can suppress temperatures significantly, whilst stalled high-pressure systems intensify heat.

Methodology

This page reviews Highest temperature in Shanghai on August 11? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi UK, which mirrors the Polymarket order book at 0% fees.

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

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.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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%.