Highest temperature in Sao Paulo on August 7?

Platform comparison

Market context

Polymarket is pricing the airport station’s 7 August maximum in São Paulo at **0% YES**, so the contract is effectively assuming the highest reading at São Paulo–Guarulhos will land outside the listed temperature band. Because settlement uses the **Daily Observations** table on Weather Underground rather than the summary “Day High & Low” box, traders should anchor to the actual station maxima at SBGR, then convert the reported Celsius figure into the market’s range. The mechanics are standard Polymarket: USDC collateral on Polygon, with conditional tokens settling off the recorded observation rather than a generic city forecast.

Historically, August in São Paulo is usually a mild winter month, with long-run daytime highs commonly in the low-to-mid 20s °C and only occasional spikes higher than that.[6][1] But current local forecasts are not uniform: one source puts Friday’s high near 25°C with dry, sunny conditions, while another weather brief and Globo’s outlook both point to 27°C with showers later in the day.[2][12] AccuWeather’s monthly view also shows early-August highs around 25°C to 27°C, with a broader August range that can reach 30°C on some days.[13][1]

For a trader, the main catalysts are the airport observation cadence and any late-day instability that can move the peak reading before the settlement cutoff. The Brazilian city forecast office has flagged cloud cover and possible isolated showers, with stronger rain and gusts later on Friday as a front edges along the coast, which can cap daytime heating if clouds arrive early.[3] Independent station data around Guarulhos late this evening already showed a mild 70°F reading with light breeze and no precipitation, suggesting the market’s final print will depend on whether earlier afternoon warmth exceeded the eventual evening cooling.[9]

Sources: 1 · 2 · 3 · 4 · 5

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.