Highest temperature in Shanghai on July 11?

Platform comparison

Market context

Shanghai Pudong International Airport faces its peak summer heat on 11 July 2026, with the settlement window closing at noon UTC to capture the day’s highest Celsius reading. Historical data confirms July is the hottest month for the region, where average daily highs reach 33°C (87°F) and frequently exceed 35°C (95°F) during sunny spells [2][6]. The current crowd-implied probability of 0% for a specific outcome suggests a stark divergence from climatological norms, as temperatures in this window rarely dip below 30°C, making a zero-probability stance on any range containing typical highs highly unusual compared to standard sportsbook lines on weather extremes.

Traders should monitor real-time METAR feeds from the National Weather Service for ZSPD, which provide the immediate ground-truth dependencies for resolution [9]. While long-term averages indicate rising solar energy and wind speeds through the month, the immediate catalyst is the forecast for gusty winds and rain on Saturday 11 July, which could suppress peak temperatures below the 35°C threshold seen in previous sunny years [8][10]. This weather pattern creates a meaningful gap between the 0% market implied probability and analyst consensus on historical heatwaves, where similar rain events have occasionally kept highs near 30°C rather than the typical 33°C–35°C range [1][8].

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 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.