Highest temperature in Chengdu on August 4?

Platform comparison

Market context

Polymarket is pricing the **34°C** contract at **41%**, which leaves the market leaning towards a warm but not exceptional peak for Chengdu Shuangliu International Airport’s highest reading on 4 August. In Polymarket terms, traders are buying and selling USDC-settled conditional tokens on Polygon, so the price reflects the crowd’s live estimate of which temperature band the Wunderground station report will land in.

That 41% reading sits in line with Chengdu’s August climate rather than any single day forecast: late-summer highs commonly sit in the low 30s Celsius, with humidity and scattered rain often muting the top end rather than pushing it higher. Recent August guides put typical daytime maxima around 30–32°C, while longer-run summaries show highs that can occasionally reach the mid-30s, which is why 34°C has become the modal outcome and 35°C remains a live alternate. The setup favours a tight distribution around the mid-30s unless cloud cover or rainfall suppresses the afternoon peak.

For traders, the main catalysts are the day’s local forecast updates, any mention of showers or thunderstorms near the airport, and the timing of the warmest afternoon hours before the settlement window closes. Chengdu’s official airport observation on Wunderground is the resolution source, so the decisive move will come from the highest recorded station temperature rather than citywide averages or nearby districts. The market description also notes that revisions to temperatures within the settlement window can still count until the first datapoint for the following date is published, which matters if late updates adjust the final printed maximum.

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 Alternative 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.

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.