Highest temperature in Beijing on August 4?

Platform comparison

Market context

Beijing’s daytime heat is still the main driver here: current August forecasts cluster around the low- to mid-30s Celsius, which fits a hot, humid late-summer pattern rather than a cool outlier. AccuWeather’s August outlook shows daily highs mostly between 79°F and 90°F, while other forecasters have Beijing’s 4 August high around 31–36°C, implying the airport maximum should land in the upper-20s to mid-30s unless cloud cover or rain caps warming.[1][3][4]

That probability mix helps explain why the crowd is not leaning to the extremes. Beijing’s August climatology is usually hot and rainy, with daytime highs commonly around 30°C to 32°C and occasional spikes above 35°C early in the month, but frequent showers and thunderstorms can quickly knock down the daily peak.[12][13][17] For a settlement source tied to Beijing Capital International Airport, the last degree or two often depends on whether afternoon convection arrives early enough to trim the highest reading.

The main catalysts to watch over the next few hours are the timing of rain, cloud breaks and any thunderstorm development, because those are the factors most likely to shift the day’s maximum away from the forecast band.[2][4][14] If precipitation arrives in the afternoon, the top reading may settle at the lower end of the expected range; if the city stays bright and humid for longer, a hotter result becomes more plausible. The market’s 0% YES pricing suggests traders are still treating the outcome as highly unlikely, but the actual airport observation later in the day will matter more than city-centre conditions.[11]

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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.

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.

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.