Highest temperature in Chongqing on August 3?

Platform comparison

Market context

Chongqing Jiangbei International Airport’s peak temperature on 3 August will be measured against a city that is structurally prone to severe summer heat. Long-run August climate references for Chongqing cluster around daytime highs in the mid-30s Celsius, with one travel guide putting the month’s high at 34.7°C and another weather service describing August as the hottest month, with daytime temperatures often in the 35–42°C range.[4][7][13][14] That makes a 0% YES price look aggressive if the contract’s YES side requires a very specific upper temperature band, because the historical baseline suggests extreme heat is normal rather than exceptional. By contrast, some forecast platforms are less bullish on outright extremes today, with outlooks closer to 34°C highs and rainy conditions, which would support a narrower outcome distribution than the most heated climatology implies.[10][16][17]

For traders, the key catalysts are the live airport observations and how much afternoon warming survives cloud, rain and humidity suppression. Current live weather readings around Chongqing show cloudier, wetter conditions than the summer average, and forecast services are already flagging showers or light rain alongside highs in the upper-20s to mid-30s Celsius.[5][9][12] That creates a clear divergence between the broader seasonal consensus and the day-of temperature path: if rain arrives early or persists, the market should lean lower than climate normals; if skies open after dawn, a spike towards the mid-30s remains plausible. In cross-platform terms, sportsbook-style weather lines and public forecasts are pointing to a fairly hot but not necessarily exceptional day, while the prediction market’s 0% YES suggests either a very tight settlement band or a pricing anomaly relative to the meteorological backdrop.[2][4][10][14]

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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

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.

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 UK 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.