Highest temperature in Shanghai on July 3?

Platform comparison

Market context

The underlying real-world event is the highest temperature recorded on 3 July 2026 at Shanghai Pudong International Airport, measured in degrees Celsius. Historical data confirms that July is Shanghai’s hottest month, with average highs reaching 37°C (87°F) and summer peaks regularly exceeding 30°C, often climbing to 35°C under clear skies [5][7]. Current market pricing on Polymarket assigns a 37% probability to the 30°C range and 35% to 31°C, contradicting the 0% crowd-implied probability for a “YES” outcome on a higher threshold, suggesting traders are misreading seasonal norms [1].

Traders should monitor the Shanghai Meteorological Bureau’s daily heat advisories and the upcoming week’s weather forecast, which currently predicts thundery showers and highs near 29°C for Hongqiao, a nearby station [3]. Recent reports indicate parts of Pudong have already exceeded 40°C this summer, with a recorded high of 40.4°C, underscoring the volatility of local heatwaves [9]. On-chain mechanics remain straightforward: positions are settled in USDC on the Polygon network using conditional tokens, meaning liquidity flows directly reflect real-time sentiment shifts as forecast updates arrive. No moralising is needed—only the facts of seasonal extremes and forecast dependencies matter for this contract.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

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.

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.

Do I need to KYC for this market?

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