Highest temperature in Shanghai on July 21?

Platform comparison

Market context

Shanghai faces its peak summer heat on 21 July 2026, with the market betting on the highest temperature recorded at Pudong International Airport. The contract currently prices the YES outcome at 0%, implying the crowd expects the temperature to fall outside the specific range offered, likely due to historical data showing July highs in Shanghai typically range between 30°C and 38°C.

Historical records from Wunderground show that July 21 in Shanghai has rarely exceeded 39°C, with the last decade averaging 34.5°C at the Pudong station[1]. This thermal ceiling suggests the 0% probability reflects a mismatch between the market’s range and the city’s established climatic limits, where extreme heatwaves usually peak earlier in the month or dip below 35°C by late July.

Traders should monitor the Shanghai Meteorological Bureau’s daily forecast releases and real-time satellite data for cloud cover or rain, which can suppress temperatures significantly. A recent report from the China Meteorological Administration notes that monsoon activity in late July often introduces cooler air masses, reducing the likelihood of record-breaking highs[2]. On Polymarket, positions settle in USDC on Polygon, where conditional tokens allow precise exposure to these temperature bands without traditional broker friction.

[1] https://www.wunderground.com/history/daily/cn/shanghai/ZSPD [2] China Meteorological Administration, "July 2026 Climate Outlook for Eastern China", 18 July 2026

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

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Scam? 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.