Highest temperature in Sao Paulo on August 7?

Platform comparison

Market context

São Paulo is set up for a fairly ordinary August winter day, with forecast highs clustered around the mid-20s Celsius rather than anything extreme. Recent local forecasts point to a maximum near 25°C to 27°C, while broader August guidance for the city sits around 23°C to 25°C, which places the market’s zero-per-cent yes price in context: the contract is paying up for a tail event that is not supported by the current weather picture.[2][7][11]

The historical framing is equally relevant. São Paulo’s August climate is typically cool and dry, with long-run daytime highs near 23°C to 25°C and only limited rainfall, so a top-of-range print at Guarulhos would still be consistent with a warm winter afternoon rather than a heatwave.[6][7] On-chain, the final payout is a simple USDC settlement tied to a single observed temperature range, so traders are really pricing the precision of the resolution source, not just the forecast headline; in markets like this, small changes in the last few degrees can move the odds sharply if late-day warming or local station readings shift the observed high.

The main catalysts are the intraday weather evolution and any late updates from local forecasters or airport-station observations. Current reporting from São Paulo points to cloud, some afternoon showers and possible thunderstorms, which can cap the high if they arrive early, while clearer breaks would allow temperatures to reach the upper forecast band.[3][10][11] Because settlement depends on the Weather Underground daily observations table for São Paulo-Guarulhos International Airport, traders should watch the station’s recorded maximum rather than a city-wide forecast, as the airport can diverge from central São Paulo by a few degrees on days with coastal cloud, wind or isolated convection.[3][14]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reads Highest temperature in Sao Paulo on August 7? 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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Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

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UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

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