Highest temperature in Shanghai on July 2?

Platform comparison

Market context

On 2 July 2026, the Shanghai Pudong International Airport Station will record its peak daytime temperature, a real-world event that determines the outcome of a prediction market currently implying zero probability for the “YES” outcome. This 0% crowd-implied probability suggests traders believe the highest temperature will fall outside the specified range, yet historical data contradicts such certainty. In July, Shanghai routinely experiences daily highs between 80°F and 93°F (26.7°C to 33.9°C), with the month’s peak average reaching 32.5°C on 29 July[4][5]. Past records show similar volatility, and even in cooler years, temperatures rarely dip below the lower threshold of the range, making a flat 0% assessment appear overly dismissive of seasonal norms[2][3].

Traders should monitor the upcoming release of Wunderground’s daily temperature logs for 2 July, which will serve as the official resolution source, alongside any sudden shifts in regional weather patterns driven by monsoon activity or urban heat anomalies. Recent forecasts from AccuWeather indicate July 2026 will maintain high thermal variability, with overnight lows between 74°F and 82°F and daytime peaks consistently exceeding 80°F[4]. While no specific weather announcements are scheduled for 2 July, the settlement window closing at 12:00 UTC means any late-morning temperature spikes could alter the outcome. Analyst consensus across cross-platform odds-comparison sites shows divergence: some sportsbooks imply a 15–20% chance of the range being hit, while prediction markets remain at 0%, highlighting a meaningful gap between trader sentiment and empirical likelihood[6]. This discrepancy warrants close attention as the day unfolds.

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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Best Prediction Markets UK. 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'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 Best Prediction Markets UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.