Highest temperature in Beijing on July 21?

Platform comparison

Market context

The market resolves on the highest official temperature recorded at Beijing Capital International Airport on 21 July 2026, so the key question is whether the airport site produced a modest summer maximum or a genuinely hot afternoon. The current crowd-implied probability of 0% YES suggests the contract is pricing the target temperature range as effectively unreachable, which is usually a sign of either an ultra-low threshold or a market that has not attracted enough participation to form a meaningful price.

For context, Beijing’s July climate is typically warm to hot, with airport readings often driven by strong daytime heating, humidity, cloud cover and any passing rain band. In markets of this type, the largest price moves usually come from a late shift in the day’s maximum rather than the morning temperature, so historical comparables matter more than the overnight forecast. If the implied probability is near zero while sportsbook-style weather derivatives or analyst expectations are broader, that divergence normally points to a contract-specific pricing issue rather than a strong independent view on the weather outcome.

Traders would normally watch short-range forecasts for Beijing Capital International Airport, any rainfall or thunderstorm timing, and whether official airport observations differ from city-centre forecasts. Because the settlement source is Wunderground’s daily history page for ZBAA, the practical dependency is the station-level recorded high rather than a general Beijing forecast; that can matter if local convection, haze, or an airport-specific wind shift keeps the peak temperature below what broader city forecasts suggest.

Methodology

We track Highest temperature in Beijing on July 21? 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

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 PolyGram. 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.

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.

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.