Highest temperature in Shanghai on August 2?

Platform comparison

Market context

Polymarket has this contract at **0% YES** on USDC-settled, Polygon-based conditional tokens, which means the market is pricing an outcome below the relevant temperature band for Shanghai Pudong International Airport on 2 August. The contract resolves from Wunderground’s daily history for that station, using the *highest* temperature recorded during the day, so the key variable is the day’s eventual maximum rather than the morning forecast or the average for the month.

The historical frame is straightforward: early August in Shanghai is usually very hot, with average highs around the low 30s Celsius and frequent readings in the mid-30s on especially warm days.[1][8][9] Recent Shanghai weather histories also show that August can produce extreme heat spikes well above typical daily highs, including 39.5°C in August 2025 and an all-time city high of 41°C on 8 August 2013, although those figures are city-level rather than airport-specific.[2][5][15] For a trader reading the order book, 0% indicates the crowd is effectively dismissing the chance of a high-end temperature bucket, despite August’s seasonal tendency towards heat.[1][8]

The main catalysts are the live temperature path at Pudong Airport, cloud cover, rainfall, and any coastal or typhoon-related air-mass shifts that could cap the day’s peak. AccuWeather’s August 2026 outlook for Shanghai has daily highs mostly in the low 30s Celsius, which is consistent with a warm, not extreme, day, but it is still only a guide and can move materially if convection or storm tracks change.[10] Because settlement uses the airport station’s recorded maximum by the cutoff window, the practical watchlist is simple: whether the day heats up after sunrise, whether showers arrive early enough to suppress the peak, and whether the final Wunderground observation confirms the band before the market closes.

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.

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 Scam? trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.