Highest temperature in Beijing on July 28?

Platform comparison

Market context

On 28 July 2026, Beijing's highest temperature will be recorded at the Capital International Airport Station and measured in Celsius. The Polymarket contract currently prices all temperature ranges at 0% implied probability, reflecting either a technical settlement quirk or genuine illiquidity across the outcome buckets. This disconnect between zero pricing and the certainty that some temperature will occur suggests traders should examine whether conditional token mechanics on Polygon are functioning normally before committing USDC.

Beijing's July temperatures cluster reliably between 25°C and 35°C, with extreme heat days occasionally pushing toward 40°C. Historical data from Wunderground shows that late July typically sees the city's hottest readings of the summer season, driven by the East Asian summer monsoon and urban heat island effects. The 2010 heatwave saw temperatures exceed 40°C for multiple consecutive days; more recently, July 2022 recorded highs around 35–37°C. These precedents establish that outcomes spanning 28–32°C, 32–36°C, and 36–40°C represent plausible settlement zones rather than edge cases.

Traders should monitor China Meteorological Administration forecasts released in early July 2026, which typically provide reliable 10–14 day outlooks for Beijing. Subtropical high-pressure systems moving northward in late July often determine whether the city experiences typical summer heat or exceptional extremes. The settlement window closes at 12:00 UTC on 28 July, giving traders roughly 24 hours after the day's peak temperature is recorded to adjust positions before Wunderground's historical data becomes the binding resolution source.

Methodology

We track Highest temperature in Beijing on July 28? 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

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 Kalshi UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Kalshi UK 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.