Pronóstico: Highest temperature in Shanghai on July 21?

Platform comparison

Market context

Shanghai's peak temperature on 21 July 2026 will be measured at Pudong International Airport Station and settled against Wunderground's historical records. The market currently prices all temperature ranges at 0%, reflecting the settlement window closure before the event occurs—a technical artifact of how Polymarket structures weather contracts on Polygon. Once 21 July arrives and the daily high is recorded, one conditional token bucket will resolve to 1 USDC whilst others expire worthless, determining payouts for positions held across the temperature bands.

July represents Shanghai's hottest month climatologically, with average highs near 32°C and extremes frequently exceeding 35°C. Historical data from Pudong station shows that temperatures above 38°C occur roughly once every three to five years during peak summer, whilst readings below 28°C are exceptionally rare in late July. The 2013 heat wave pushed Shanghai to 40.8°C, and 2022 saw sustained temperatures above 35°C throughout the month. These precedents suggest the market's eventual resolution will likely cluster in the 33–37°C range, though anomalous weather patterns could shift outcomes significantly.

Traders monitoring this contract should track seasonal atmospheric patterns and any tropical cyclone activity in the Western Pacific during early-to-mid July 2026, as typhoons can suppress temperatures dramatically or intensify heat depending on their trajectory. China Meteorological Administration forecasts and regional pressure systems become actionable signals roughly two weeks before settlement. Wunderground's historical database occasionally experiences minor discrepancies with official Chinese meteorological records, though Pudong station data typically aligns closely with published figures.

Methodology

We track Pronóstico: Highest temperature in Shanghai on July 21? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

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

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 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.

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.