Highest temperature in Beijing on August 4?

Platform comparison

Market context

Polymarket is pricing this Beijing airport temperature contract at **0% YES** right now, so the on-chain market on Polygon implies almost no chance that the eventual settled range will be the one currently being bid up. Because the market resolves off the highest reading at Beijing Capital International Airport Station in Wunderground’s daily history page, the trade is really about the airport’s realised maximum, not city-wide averages or forecasts for central Beijing.

Historical and comparable cases point to a hot, humid late-summer baseline. August in Beijing is typically described as hot and rainy, with average highs around 30–31°C and some forecasts clustering the first week of August in the low-to-mid 30s Celsius; several current projections for 4 August sit around 31–36°C, which is consistent with the broader seasonal range. That backdrop matters because even modest forecast misses can shift the final settlement band by a degree or two, especially when cloud cover or storms cap daytime heating.

For traders, the key catalyst is the day’s actual airport observation sequence: once the station posts its highest temperature for 4 August and Wunderground updates the history page, the market’s conditional tokens should converge towards the range containing that reading. In practical terms, the watchlist is the late-morning to afternoon Beijing weather evolution, any thunderstorm or rainfall timing, and whether the airport records a brief spike before cloud and precipitation suppress the peak. The contract settles in USDC, so the move in price is tied directly to how the market reassesses the probability of each Celsius bucket as new observations come through.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Beijing on August 4? 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

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

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.

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.