Highest temperature in Shanghai on August 8?

Platform comparison

Market context

Shanghai’s height of summer usually sits in the low-30s Celsius, but the contract settles on the *single highest reading* recorded at Shanghai Pudong International Airport Station in Weather Underground’s Daily Observations table, not the headline high shown elsewhere. That makes the market more about the day’s realised intraday peak than the broader daily forecast, and it leaves room for a brief convective spike even if the city spends much of the day under rain or cloud. Current public forecasts are broadly hot, with AccuWeather showing around **35°C** and other services clustering in the **31–35°C** band for Shanghai on 8 August, which is consistent with a summer peak that can still overshoot ordinary daily averages.[1][3][4][6][14]

The crowd-implied **0% YES** suggests the market is pricing the outcome as effectively settled against the target range, but that needs to be read carefully in a weather contract because late-morning heating, thunderstorm boundaries, and station-specific observation timing can all matter more than citywide summaries. Comparable August climatology for Shanghai points to average highs near **31–32°C**, with long-run daily highs often sitting a few degrees above that and rainfall common enough to suppress the realised maximum on some days.[1][9][13][18] In other words, the relevant question is not whether Shanghai is warm, but whether the Pudong station prints a temperature that lands inside the contract’s specified Celsius band before observations close.

For traders, the key catalysts are the live Wunderground observation feed, any short-lived thunderstorm or typhoon-related disruption, and whether forecast-heavy morning heat is followed by cloud cover or rain before the day’s maximum is logged.[2][3][8][15] AccuWeather’s wording already flags a morning thunderstorm and showers later, while Wunderground is showing **92°F/81°F** with an update in Shanghai, implying a warm baseline that could still be capped if rain develops early.[3][8] On the crypto side, the payout is a straightforward USDC-style binary settlement, so the market is mainly about event resolution rather than BTC or ETH direction unless wider risk appetite shifts liquidity across prediction markets.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reads Highest temperature in Shanghai on August 8? 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.

UK Frequently Asked Questions

What are crypto prediction markets?

Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.

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USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

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