Highest temperature in Chengdu on July 30?

Platform comparison

Market context

Chengdu’s official airport reading for 30 July will decide whether this contract lands in the higher summer bands or stays in a milder range. The market is currently priced at 0% YES, which is far below the broad weather consensus: several forecast sources put Chengdu’s daytime high around 31–35°C, with some expecting a cooler, rain-affected day near 28–29°C and others allowing for a hotter outcome around 33–35°C[2][3][10][12][14].

Historically, Chengdu in late July is warm, humid and rain-prone rather than consistently extreme, but that still leaves room for a wide intraday spread because the settlement uses the *highest* temperature recorded at Chengdu Shuangliu International Airport Station, not the daily average or evening low[7][16]. On that basis, a 0% YES view implies the crowd is effectively expecting the final print to fall outside the contract’s winning range, even though the published forecasts cluster well above early-summer norms and many comparable days in the region have highs in the low- to mid-30s Celsius[1][3][7][11]. That makes the contract look markedly cheaper than the weather models, although airport observations can undershoot city forecasts if rain arrives early or persists through the warmest part of the day[2][12].

For traders, the key catalyst is the day’s live evolution at Chengdu airport: cloud cover, timing of showers, and whether the afternoon heating window opens before heavier rain moves in. Recent forecasts diverge enough to matter, with some services showing heavy rain and a high near 28°C, while others keep Chengdu closer to 31–35°C and still assign meaningful rain chances[2][3][10][14]. Because the market settles on the Wunderground airport station reading, any short-lived burst of sun can lift the maximum even if the broader city forecast remains wet, while an early storm line would keep the printed high suppressed[2][14].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Chengdu on July 30? 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 Best Prediction Markets. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets 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.