Highest temperature in Shanghai on August 8?

Platform comparison

Market context

Shanghai’s temperature on 8 August will be judged by the highest reading at Pudong Airport, not the headline “day high” shown elsewhere, so the relevant question is whether the airport station reaches the contract’s Celsius band during the afternoon. The market’s current 0% YES implies the crowd is treating a qualifying high as effectively impossible, even though commercial forecasts still show a warm, unsettled day: AccuWeather has Shanghai around 93°F/33°C with thunderstorms and showers, while Weather Underground’s own city page shows 92°F/81°F and notes cooler conditions than yesterday.[2][3][8]

On comparable August Shanghai days, the distribution usually sits in the low 30s Celsius, with long-run August averages near 29–31°C and typical highs around 32–34°C, so this contract is sensitive to whether the airport keeps just below or briefly touches the next bracket.[1][10][14][15] That matters because different platforms are already clustered around the same rough range: AccuWeather, Timeanddate and Chinese forecast pages mostly point to highs near 31–34°C, which is materially higher than a 0% market price would suggest if the settlement band includes the forecast peak.[4][6][10]

The main catalysts are timing and localisation rather than policy or schedule risk. Traders should watch the afternoon thunderstorm risk, which can cap the daily maximum even on a hot day, and the exact Weather Underground observation updates for Shanghai Pudong Airport before the settlement window closes at noon UTC, because the market resolves to the station’s recorded observation, not the summary tile.[2][3][8] For cross-platform comparison, the implied 0% YES looks far below the prevailing forecast cluster, so any move in the airport observation towards the low-to-mid 30s Celsius would likely matter more than changes in broader city forecasts.[2][6][8]

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

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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 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.