Highest temperature in Shanghai on August 11?

Platform comparison

Market context

Shanghai's peak temperature on 11 August 2026 will be measured at Pudong International Airport Station and resolved against Weather Underground's Daily Observations table rather than its Day High & Low summary—a distinction that matters when platforms diverge on data hierarchy. The current 0% implied probability reflects either extreme confidence in a specific temperature band or minimal trading activity on this particular date-location pair.

Historical August temperatures in Shanghai cluster between 32–36°C, with occasional peaks above 37°C during heat waves. The city experiences its most intense heat in mid-August when the East Asian summer monsoon interacts with the Tibetan high-pressure system. Comparable markets on Polymarket and Kalshi have shown that weather resolution disputes often hinge on source selection—Polymarket's reliance on third-party APIs versus Kalshi's direct institutional feeds can produce different settlement outcomes. Traders should note that Weather Underground's Daily Observations table, which this market specifies, pulls from airport stations rather than urban centres, typically recording slightly lower temperatures than downtown readings.

Catalysts include the China Meteorological Administration's seasonal forecasts (usually issued in June) and any tropical cyclone activity in the Western Pacific during late July and early August, which can suppress temperatures or trigger sudden spikes. The settlement window closes at 12:00 UTC on 11 August 2026, giving traders access to morning observations but not the full day's range—a timing constraint worth comparing against Betfair's weather markets, which often settle after midnight local time. Fee structures across platforms (Polymarket's 2% maker/taker versus Kalshi's variable spreads) will influence whether the 0% probability reflects genuine market consensus or insufficient liquidity.

Methodology

We read Highest temperature in Shanghai on August 11? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live mid is the canonical probability; the side-by-side columns benchmark fees, KYC, settlement currency and deposit rails so you can choose the venue that fits your jurisdiction and trade size.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Robinhood Prediction Markets has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.