Highest temperature in Shanghai on August 20?

Platform comparison

Market context

Shanghai's highest temperature on 20 August 2026 will be recorded at Pudong International Airport Station and resolved via Weather Underground's Daily Observations table. The market currently shows 0% implied probability across all temperature ranges, suggesting either early-stage liquidity or a data-loading artefact typical of weather markets with extended settlement windows. Resolution hinges on the granular hourly readings in Weather Underground's primary data feed rather than the Day High & Low summary, a distinction that occasionally produces discrepancies of 1–2 degrees Celsius in humid subtropical climates.

August in Shanghai historically peaks between 32–36°C, with 2023 recording 38.1°C and 2022 reaching 40.9°C during extreme heat events. The 20th typically sits near mid-month intensity; comparing adjacent years reveals volatility of ±3–4°C depending on Pacific typhoon activity and upper-level ridge positioning. Traders should cross-reference China Meteorological Administration forecasts and tropical cyclone tracking data from the Joint Typhoon Warning Center, as late-summer storm systems can suppress temperatures by 5–8°C within 48 hours of landfall.

Near-term catalysts include the Asian summer monsoon pattern, which enters its most active phase in mid-to-late August, and any tropical disturbances developing across the Western Pacific. USDC settlement on btc-prediction.bet will execute against the resolved temperature band; traders monitoring funding rates on perpetual weather derivatives elsewhere may detect early positioning shifts if model consensus shifts materially. Historical Weather Underground data for Shanghai remains reliable; the primary risk lies in station maintenance windows or sensor recalibration during the settlement period.

Methodology

This page reads Highest temperature in Shanghai on August 20? on-chain. Polymarket's quote comes directly from the Polygon order book — the only comparable venue with on-chain settlement. Kalshi (USD, off-chain), Betfair (GBP/EUR, off-chain) and Manifold (play-money) are listed alongside for venue context. Every CTA routes to BTC Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

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