Highest temperature in Shanghai on May 23?

Platform comparison

Active sub-markets

Market context

Shanghai's weather on 23 May 2026 will determine which temperature band captures the day's peak reading at Pudong International Airport. The market currently prices all temperature ranges at zero, reflecting either extreme uncertainty about settlement mechanics or genuine difficulty in forecasting conditions eighteen months ahead. On Polygon, traders are holding conditional tokens denominated in USDC, with resolution tied to Wunderground's historical weather database—a dependency that introduces both clarity (automated data source) and risk (potential data corrections after settlement closes).

May in Shanghai typically sits within the late-spring transition toward summer heat. Historical records show daily highs ranging from 26°C to 32°C during this period, with occasional spikes above 33°C during early heat waves. The 0% crowd probability suggests traders are either waiting for seasonal patterns to crystallise closer to the event date or treating the contract as too granular for meaningful prediction at this distance. Comparable weather markets on Polymarket have shown that temperature-band contracts attract liquidity only when the event window narrows to weeks rather than months.

Catalysts shaping this market's evolution include China's meteorological agency forecasts (typically issued monthly with increasing precision), any El Niño or La Niña patterns affecting East Asian summer onset, and broader climate data releases. The Shanghai Municipal Meteorological Bureau publishes seasonal outlooks that traders monitor for directional signals. Settlement hinges entirely on Wunderground's historical archive pull, making data availability and any corrections to their database a material consideration for position holders.

Methodology

We track Highest temperature in Shanghai on May 23? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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 it cost to trade on PolyGram?

Zero. PolyGram routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

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?

Not under $1,500 of lifetime trading volume. Above that threshold, PolyGram triggers a quick verification flow that finishes in minutes.