Highest temperature in Guangzhou on July 25?

Platform comparison

Market context

Guangzhou will experience peak summer heat on 25 July 2026, with the settlement hinging on the single highest temperature reading recorded at Baiyun International Airport Station throughout that calendar day. The resolution mechanism ties directly to Wunderground's historical weather database, which logs hourly observations and derives daily maxima automatically. For programmatic traders, this creates a straightforward data dependency: the market resolves once Wunderground publishes its 25 July entry, typically within 24–48 hours of the settlement window close.

Guangzhou's July temperatures have historically clustered between 32–36°C, with extremes occasionally reaching 37–38°C during heat waves. The 0% crowd probability suggests either extreme confidence in a specific temperature range or minimal trading activity. Comparable markets on Wunderground-sourced weather data show resolution typically occurs without dispute, as the platform's methodology is transparent and automated. Historical records from the past five years indicate July peaks in Guangzhou rarely exceed 37°C, though the 2022 summer saw several days above 36°C.

Traders should monitor China Meteorological Administration forecasts released in early July 2026, which provide 10–15 day outlooks for Guangzhou. Tropical cyclone activity in the South China Sea during late July can suppress temperatures through cloud cover and rainfall, whilst high-pressure systems drive sustained heat. The specific airport station location matters: Baiyun sits north of central Guangzhou and may record marginally different readings than urban core stations. Automated conditional orders can be structured to resolve against Wunderground's API if available, though manual verification against the historical page remains the standard approach for settlement confirmation.

Methodology

We track Highest temperature in Guangzhou on July 25? 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.

FAQ

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.

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.