Highest temperature in Chengdu on July 31?

Platform comparison

Market context

Polymarket is pricing the **highest temperature at Chengdu Shuangliu International Airport Station on 31 July** at **0% YES**, so the contract is trading as if there is no market for a qualifying outcome in the currently visible range. The market settles against the day’s peak reading from the Wunderground station page, and the position is held through Polymarket’s usual USDC-settled, Polygon-based conditional tokens, so traders are really taking a view on the station maximum rather than on citywide averages or headline forecasts.

The historical and forecast backdrop does not point to an extreme today by Chengdu standards. July is usually warm and humid, with long-run summaries putting daytime highs around the low 30s Celsius and plenty of rain, while individual 31 July forecasts from several weather services cluster around roughly 30–35°C, with some models showing a brief afternoon spike above 35°C and others nearer 33°C. That mix matters because the market resolves on the single highest station reading, not the average daytime temperature, so a short-lived clear interval or a storm break can change the winning bucket more than the daily mean.

Traders should watch the local forecast updates through the afternoon, plus any changes in convective rain timing, cloud cover and wind that affect whether the airport station briefly heats up before showers arrive. Chengdu weather services currently show a humid, unsettled pattern with rain chances and midday warmth, which is the main dependency for the eventual max reading rather than any scheduled announcement. Because the settlement window closes at 12:00 UTC, the position is exposed to the final hours of local daytime heating in Sichuan before Wunderground’s recorded daily high is fixed.

Sources: 1 · 2 · 3 · 4 · 5

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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Alternative 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Alternative UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.