Highest temperature in Shanghai on July 13?

Platform comparison

Market context

Shanghai faces its peak summer heat on 13 July 2026, with the Shanghai Pudong International Airport Station expected to record a daily high well above 30°C. Historical data confirms that mid-July in Shanghai routinely sees temperatures exceeding 35°C, often reaching 38°C in recent years, making a 0% crowd-implied probability for any meaningful heat event appear statistically anomalous given the season’s typical intensity[3][6].

Comparable cases from July 2025 show highs peaking at 38°C, while 2026 forecasts for the airport indicate daily highs ranging from 30°C to 37°C (86°F to 97°F), suggesting the market’s current pricing may diverge sharply from climatological reality[1][6]. This 0% implied probability contrasts with analyst consensus on summer heat in the region, where temperatures consistently breach 30°C, raising questions about whether the line reflects a data error or an extreme outlier expectation not supported by historical patterns[3][5].

Traders should monitor real-time updates from Wunderground and local meteorological bulletins for any sudden shifts in cloud cover or precipitation that could suppress temperatures, though such events are rare in mid-July[3]. The settlement depends entirely on the highest temperature recorded at the Pudong station by 12:00 UTC on 13 July, with no announcements expected to alter the baseline forecast before the window closes[4]. Current forecasts from AccuWeather and Yr.no indicate partly cloudy conditions with a maximum of 31–32°C, reinforcing the likelihood that the market’s zero probability is misaligned with observed weather trends[1][10].

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

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 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.