Highest temperature in Chengdu on August 2?

Platform comparison

Market context

Chengdu’s airport will need to print the day’s **highest temperature** by the end of the settlement window, with the contract resolved against the Wunderground history page for Chengdu Shuangliu International Airport Station. The crowd-implied **0% YES** is far below the August climatology for the city, where the typical high is around **31–32°C** and early-August readings often sit in the upper 20s to low 30s Celsius, so a zero-priced contract is only sensible if traders expect the source station to remain materially cooler than normal or if they are discounting the market’s specification. [1][5][6][9][18][20]

Historical comparisons argue against treating this as an extreme-cold outcome by default. August is generally Chengdu’s hottest month, with average maximum temperatures around **31°C** and occasional spikes into the **upper 30s°C** in heatwave years, including an all-time city high of **39°C** reported for 23 August 2022. At the airport station, recent historical weather pages show similarly warm summer profiles, which makes the implied probability look detached from the broader climatology unless the marketplace is unusually skewed towards a lower temperature band than consensus weather expectations. [8][11][14]

The main catalysts are straightforward: the eventual airport observation on Wunderground, any short-lived rain bands or cloud cover that suppress the afternoon high, and whether the day’s peak occurs early before heating fully develops. Chengdu’s summer humidity is typically high, but precipitation can still cap the maximum if convection arrives during the warmest hours; the most relevant watch item is the live airport station record rather than citywide forecasts, because settlement depends on that specific source and not on general Chengdu conditions. [1][5][12][16]

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

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.

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets 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.