Highest temperature in Chengdu on July 20?

Platform comparison

Market context

Chengdu’s highest temperature on 20 July 2026 will be recorded at the Shuangliu International Airport Station, with settlement based on Wunderground’s daily maximum in degrees Celsius. Historically, July in Chengdu sees average highs of 31°C, though peaks frequently exceed 35°C during heatwaves, and humidity often reaches 75%, creating boisterous, oppressive conditions [1]. The current 0% crowd-implied probability for any specific range suggests traders are either misreading the event’s certainty or betting on an extreme outlier; in comparable years, temperatures above 30°C are near-guaranteed, making a zero-probability stance on plausible ranges statistically anomalous.

Programmatic traders should monitor real-time Wunderground feeds for the Shuangliu station, automating conditional orders that trigger when the daily maximum crosses predefined thresholds. Key catalysts include the regional weather forecast for the Sichuan Basin, which typically issues heat advisories 2–3 days ahead of extreme temperatures, and any sudden shifts in monsoon activity that could suppress highs [2]. Since July is also China’s school holiday period, increased urban heat retention from crowds may amplify temperatures, a factor worth encoding into predictive models. Traders must verify the exact timestamp of Wunderground’s data update to avoid latency errors in execution.

Sources: 1 · 2

Methodology

We track Highest temperature in Chengdu 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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

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 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.

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.