Highest temperature in Beijing on July 20?

Platform comparison

Market context

Beijing’s summer heat on 20 July 2026 hinges on whether the Beijing Capital International Airport Station records a peak above 35°C, the threshold for the YES outcome. With the crowd-implied probability at 0% YES, the market treats a scorching day as virtually impossible, yet July in Beijing routinely sees highs between 30°C and 37°C, making this a stark contrarian signal.

Historical data from Wunderground shows that on 20 July in recent years, Beijing’s airport station hit 36.2°C in 2023, 34.8°C in 2022, and 37.1°C in 2021, confirming that temperatures above 35°C are not anomalies but recurring features of mid-summer [1]. The current 0% pricing ignores this pattern entirely, suggesting the consensus is overly anchored to short-term cooling trends or a misread of the settlement window’s end date, creating a clear value spot for those willing to bet against the crowd.

Traders should monitor the China Meteorological Administration’s daily forecast updates and the 5-day extreme heat bulletin, which often precede spikes in airport station readings. A recent report from Xinhua News Agency noted that Beijing entered a prolonged heatwave period from 15 July, with officials warning of sustained highs above 35°C through 22 July, a catalyst that directly supports the YES outcome [2]. The settlement window closing at 12:00 UTC on 20 July means any afternoon peak after that time won’t count, but the morning-to-midday window remains wide open for a record-breaking day.

Methodology

We track Highest temperature in Beijing on July 20? 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

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

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.

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 Who Will Win 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.