Highest temperature in Chengdu on July 25?

Platform comparison

Market context

Chengdu faces a typical late-July heat pattern, with atmospheric conditions favouring sustained high temperatures across the basin. The city's geography—surrounded by hills that trap warm air—creates a natural heat sink during summer months. Current meteorological data points to continued pressure from the western Pacific subtropical high, which has dominated the region through mid-July. No significant weather system is forecast to break this pattern before the 25th, meaning conditions should remain stable rather than volatile.

Historical records from Chengdu Shuangliu Airport show July temperatures consistently exceed 35°C, with peaks frequently reaching 37–39°C during the month's latter half. The station's 30-year average high for late July sits around 32–33°C, though actual daily maxima typically run 3–5°C above this figure. The 0% crowd probability reflects either market illiquidity or misalignment with seasonal norms; comparable years suggest the likelihood of exceeding 35°C on any given late-July day sits well above zero.

Traders should monitor the China Meteorological Administration's official forecasts, updated daily, for any shift in the subtropical high's position or strength. Monsoon activity from the south could theoretically introduce cloud cover and precipitation, though current model consensus shows this remaining unlikely through the 25th. Real-time observations from Wunderground will be the settlement source, so familiarity with how that platform records airport station data—particularly timing of peak readings—matters for precise range selection.

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

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 Prediction Today. 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 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 fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

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.