Highest temperature in Shanghai on July 18?

Platform comparison

Market context

Shanghai's highest temperature on 18 July 2026 will be recorded at Pudong International Airport Station and resolved against historical weather data. The crowd currently assigns zero probability to any outcome, suggesting either extreme confidence in a particular temperature band or insufficient liquidity and trader participation at settlement time.

July in Shanghai typically sees peak summer heat, with daily highs routinely exceeding 32°C and occasionally reaching 35–37°C during heat waves. The city's thirty-year average for mid-July sits around 32–33°C, though extreme events have pushed readings above 40°C in recent decades. The 0% crowd probability likely reflects traders anchoring to seasonal norms rather than pricing genuine uncertainty across temperature ranges. Historical volatility in Shanghai's summer weather—driven by typhoon proximity, urban heat island effects, and monsoon patterns—suggests meaningful probability should distribute across multiple bands rather than concentrating entirely on one outcome.

Monitoring China's meteorological forecasts in early July 2026 will be essential, particularly alerts regarding tropical cyclone activity in the Western Pacific, which can suppress temperatures or trigger sudden heat spikes depending on storm track and timing. The East Asian summer monsoon's strength that season will also influence whether high-pressure systems dominate (favouring extreme heat) or whether moisture-laden systems moderate conditions. Traders should watch for any official heat warnings issued by the China Meteorological Administration in the week preceding 18 July, as these often signal confidence in sustained high temperatures rather than isolated daily peaks.

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

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 Who Will Win 2026 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.