Highest temperature in Sao Paulo on July 9?

Platform comparison

Market context

On 9 July 2026, the Sao Paulo-Guarulhos International Airport Station will record its peak temperature for the day, a real-world event that determines the outcome of a prediction market currently assigning a 0% chance to the 23°C threshold. Historical data frames this probability starkly: July is São Paulo’s coldest month, with average highs around 22°C (72°F)[3], and recent records show July 2023 was the hottest in 174 years yet still averaged only 16.92°C[2]. The consensus is heavily locked on 22°C, which the market prices at 98% probability, while 23°C sits at under 1%[1]. This tight clustering suggests the crowd views any deviation above 22°C as an extreme outlier, making the 0% implied probability for 23°C a reflection of deep seasonal confidence rather than a mere oversight.

Traders should monitor the stable winter high-pressure system currently dominating the region, which meteorological models predict will sustain afternoon highs between 22–24°C at official stations like Guarulhos[1]. While recent heatwaves have scorched Rio de Janeiro with record indices of 62.3°C, São Paulo’s urban climate and July seasonality act as a natural underdog against such extremes[4]. The key catalyst is the Wunderground data release for the specific station, which will confirm if the high-pressure system holds or if a transient warm front pushes temperatures to the contrarian 23°C mark. Given the 98% consensus on 22°C, any value spot would likely lie in betting against the crowd if late-model adjustments suggest a pressure break, though current data supports the underdog 22°C outcome as the dominant favourite.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Sao Paulo on July 9? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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 Who Will Win 2026. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Who Will Win 2026 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.