Highest temperature in Sao Paulo on July 6?

Platform comparison

Market context

The real-world event at hand is the maximum temperature recorded on 6 July 2026 at São Paulo-Guarulhos International Airport, with resolution tied to Wunderground’s daily high in degrees Celsius. While one prediction market shows a 0% implied probability for a specific outcome, Polymarket’s leading contract pins the expected high squarely in the 24–25°C band, assigning 49% to 24°C and 21% to 25°C, for a combined 61% crowd-implied probability. This divergence highlights how cross-platform odds can vary significantly even for identical weather contracts.

Historical patterns frame this narrow range as highly plausible: July in São Paulo typically sees daily highs around 22–23°C, rarely falling below 18°C or exceeding 27°C, with average highs near 22.7°C on 3 July and 21.6°C at the month’s start. Early July afternoon highs commonly cluster between 18°C and 22°C, though recent model guidance and official data push the expected peak slightly higher into the 24–25°C zone, aligning with current trader sentiment.

Traders should monitor the upcoming 72-hour forecast updates from AccuWeather and the daily Wunderground release for SBGR, as any sudden shift in cloud cover or wind patterns could alter the high. AccuWeather’s July 2026 forecast for São Paulo indicates daily highs ranging from 66°F to 78°F (18.9°C to 25.6°C), with an average of 73°F (22.8°C), suggesting the 24–25°C band remains within normal seasonal variance. No major weather announcements are scheduled, but real-time data from PredictWind and Weather Spark will be critical as settlement nears.

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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.