Highest temperature in Chengdu on July 11?

Platform comparison

Market context

Chengdu’s highest temperature on 11 July 2026 will be recorded at the Shuangliu International Airport Station, with resolution based on Wunderground’s daily maximum in degrees Celsius. The market currently implies a 0% probability for any specific outcome, yet trader consensus clusters tightly around 32–34°C, with 34°C as the frontrunner at 27% and 35°C at 22% [1]. This divergence between the zero-implied probability and the ensemble spread suggests a data lag or unresolved settlement logic rather than a genuine belief in an impossible event.

Historically, July is Chengdu’s hottest month, with average highs of 26–30°C and frequent peaks reaching 38°C during fuggy, high-humidity periods [6][8]. Comparable Polymarket events show similar volatility: on 9 July 2026, the market resolved to 39°C with 100% certainty, indicating that extreme heat days are not anomalies but expected features of the season [2]. Programmatic traders should treat the 0% as a transient signal, using historical variance and model spreads to back-test conditional orders rather than assuming market silence implies no risk.

Key catalysts include real-time Wunderground updates for ZUUU and regional ensemble model adjustments, which currently show tight spreads across global and regional forecasts [1]. Traders should monitor hourly temperature feeds and any sudden shifts in humidity or cloud cover, as these directly impact the daily maximum. No official weather announcements are scheduled, but dependencies on Wunderground’s data pipeline mean resolution hinges entirely on automated ingestion—making script-based monitoring of the API endpoint the most reliable utility for position management.

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

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 Polymarket Bot UK. 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Bot UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.