Highest temperature in Chengdu on August 17?

Platform comparison

Market context

Polymarket is pricing Chengdu’s 17 August high at 0% for YES, which leaves the contract effectively unmoved from the market’s current expectation even though the relevant settlement source is the Daily Observations table for Chengdu Shuangliu International Airport Station, not the headline day-high summary. On the current book, traders are not paying up for a hotter-than-usual print before the noon UTC close of the settlement window.

That low price sits against a climatology that keeps Chengdu’s mid-August highs in the low 30s Celsius, with airport-based averages around 30°C and day-to-day highs often clustering near 31–34°C. Recent forecast snapshots are mixed: some services point to 31–34°C, while others show a cooler, rain-affected day around 26–28°C, which is why the exact station observation matters more than citywide weather summaries. Historical August patterns also show humidity and showers can cap the realised maximum even when the broader forecast looks hot.

For Polymarket users, the practical catalysts are the updated airport observations through the day, any late changes to the local forecast, and whether convection or rainfall arrives early enough to suppress the afternoon peak. Because the contract settles on USDC-backed conditional tokens on Polygon, the trade is really about the final published station maximum rather than the felt temperature or the broader Chengdu forecast. In this kind of market, the last few degrees before 12:00 UTC are what determine whether the range containing the recorded high is hit.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Chengdu on August 17? 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

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.

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 PolyGram. 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.

Do I need to KYC for this market?

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

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.