Highest temperature in Beijing on June 28?

Platform comparison

Market context

Beijing is experiencing blistering heat as summer heatwaves return to the capital, with temperatures soaring past 41°C in late June. This real-world surge frames the current prediction-market implied probability of 0% YES for the contract tied to the highest temperature at Beijing Capital International Airport on 28 June 2026. The market resolves based on Wunderground data for that specific day, yet the crowd’s dismissal of higher ranges appears stark when weighed against historical patterns.

Historical data shows Beijing’s late-June highs typically span from the upper 20s to the low 40s in degrees Celsius, with 33°C sitting near the lower end of the summer range [4]. In 2023, the city recorded 41.1°C on 22 June, shattering the June record and marking its second-highest temperature ever [1][9]. Average June highs in Beijing rarely fall below 73°F (23°C) or exceed 96°F (36°C), though extreme heatwaves have pushed temperatures well beyond this band [2]. The 0% probability suggests traders expect a cooler day, yet recent records indicate such an outcome is statistically improbable.

Traders should monitor official heatwave advisories and scheduled weather bulletins from Chinese authorities, as the fourth and strongest heatwave in mid-2023 lasted from 21 to 30 June and drove temperatures above 41°C [7]. No major announcements have altered the forecast for 28 June 2026, but the persistence of high-pressure systems could sustain extreme heat. Lines.com notes that 33°C is near the lower threshold for typical summer highs, implying a meaningful divergence between sportsbook lines, prediction-market odds, and analyst consensus on this contract [4]. The absence of cold-air forecasts further supports the likelihood of elevated temperatures.

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 Best Prediction Markets. 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'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.

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.