Highest temperature in Shanghai on August 1?

Platform comparison

Market context

Shanghai Pudong International Airport Station will set the result off the day’s **single highest recorded temperature** in degrees Celsius, so the practical question is whether the afternoon peak clears the next range threshold before the daily reset. August is normally Shanghai’s hottest month, with average highs around 31–32°C and frequent days above 35°C, while historical records for the city show that extreme heat can push far higher in heatwave conditions.[7][15]

For a market that currently implies **0% YES**, the historical frame is that Shanghai regularly produces mid-30s readings in August, but the airport location is usually a little less extreme than the city centre because coastal airports benefit from sea influence and stronger ventilation. Past August references still show typical highs near 30.7°C to 32°C and occasional spikes into the high-30s, including a recent local August peak of 39°C, so the relevant comparison is not the monthly average but the tail risk of a short-lived heat surge.[6][9][12]

A programme-driven trader would watch the forecast path for the airport station, then map the expected maximum to the market’s temperature brackets and update orders as new runs arrive. The main catalysts are heat advisories, typhoon tracks, cloud cover, rainfall timing, and sea-breeze strength; Shanghai’s weather bureau has repeatedly issued high-heat alerts in August when inland heat builds and the city can approach 40°C, so any forecast shift towards a stagnant, sunny, low-wind setup matters more than the broader monthly average.[4][11][15]

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 Bot UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 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.

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.