Highest temperature in Sao Paulo on June 30?

Platform comparison

Market context

On 30 June 2026, the real-world event determining this market’s outcome is the highest temperature recorded at São Paulo–Guarulhos International Airport, measured in degrees Celsius and sourced from Wunderground. In prediction markets, a YES share pays out if the temperature falls within the specified range (here, likely an extreme high), while a NO share wins if it does not. The crowd currently assigns a 0% probability to YES, implying near-certainty that the day will not reach an unusually hot threshold.

Historically, June in São Paulo is mildly cool and breezy, with average highs of 23°C and lows of 13°C, often described as humid but cool[1]. The city’s hottest recorded day reached 38.5°C, but that occurred in November 2023, not during the winter months[2]. Recent data from mid-June 2026 shows a peak of 26°C (78.8°F) on 22 June, reinforcing the pattern of moderate temperatures[3]. These comparable cases support the market’s current 0% YES probability, as extreme heat is exceptionally rare in June.

Traders should monitor daily weather bulletins from Brazil’s National Meteorological Institute (INMET) for any unexpected heatwave announcements, though such events are uncommon in winter. No major climate catalysts—such as volcanic activity or sudden shifts in the Atlantic trade winds—are currently forecast to disrupt seasonal patterns. Given the consistent historical data and lack of imminent anomalies, the market’s pricing aligns with observed reality.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Sao Paulo on June 30? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Prediction Market UK, which mirrors the Polymarket order book at 0% fees.

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 Prediction Market UK. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Market UK 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.