Highest temperature in Chengdu on August 18?

Platform comparison

Market context

Chengdu will experience peak summer heat on 18 August 2026, with the settlement hinging on the highest temperature recorded at Shuangliu International Airport's meteorological station. The market resolves to a specific temperature range based on data from Weather Underground's Daily Observations table—the granular, minute-by-minute readings rather than the summary high-low figures. This distinction matters for programmatic traders: the Daily Observations feed captures intraday temperature peaks that may differ from rounded daily summaries, requiring API-level access to the raw dataset rather than reliance on published forecasts.

Chengdu's August temperatures have historically ranged between 32–37°C, with occasional peaks exceeding 38°C during heat waves. The 0% crowd probability suggests markets are pricing in either extreme confidence in a specific temperature band or insufficient liquidity to establish meaningful odds. Comparable August settlements at Shuangliu show that whilst the city regularly hits mid-30s, the variance between years depends on monsoon timing and upper-atmosphere pressure patterns. Traders should cross-reference historical Weather Underground records for the same station to calibrate expectations against the specific measurement methodology.

China's meteorological authority typically issues heat alerts 48–72 hours before extreme conditions, with announcements published through state media and the China Meteorological Administration website. August 2026 forecasting becomes actionable from early August onwards; traders should monitor seasonal outlooks from the National Climate Center and track real-time atmospheric conditions via model consensus (GFS, ECMWF) as the date approaches. Conditional orders tied to heat advisory triggers could automate position adjustments if forecasts shift materially.

Methodology

We track Highest temperature in Chengdu on August 18? 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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Polymarket Review 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%.