Highest temperature in Shanghai on July 27?

Platform comparison

Market context

The key real-world event is the highest temperature recorded at Shanghai Pudong International Airport on 27 July 2026, which will be taken from the Wunderground daily history page for the station. The market is currently showing 0% implied probability for a YES outcome, while live weather sources already point to a very warm day: BBC Weather shows 22°C at the time of checking, AccuWeather lists 91°F with a RealFeel of 101°F, and the Met Office forecast indicates daytime maxima in the mid-to-high 30s Celsius. [1][2][3]

That framing matters because Shanghai in July is normally hot, humid and rain-prone rather than cool, with typical monthly averages around 32°C for the high and 135 mm of rainfall across the month. Travel-focused climate summaries therefore support a distribution skewed towards elevated daytime highs, but not necessarily extreme spikes every day; a forecast maximum of 35-37°C from the Met Office sits in line with a plausible summer peak, which helps explain why a zero-priced contract may simply reflect illiquidity or a market underweighting the chance of the station’s recorded high landing in the upper bins. [2][4]

For traders, the main catalyst is the intraday evolution of the marine monsoon pattern around Shanghai: cloud cover, afternoon showers and thunderstorms can suppress or delay the day’s peak temperature, while a break in rain can lift the airport reading quickly. The relevant dependency is the station-specific maximum on the Wunderground history page rather than city-wide weather reports, so small spatial differences between Pudong and central Shanghai can matter; comparison across sportsbooks is limited here because this is a weather-resolution contract rather than a standard event line, leaving prediction-market pricing and meteorological forecasts as the main signals. [2][4]

Sources: 1 · 2 · 3 · 4

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

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 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.

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.