Highest temperature in Toronto on August 12?

Platform comparison

Market context

On 12 August 2026, Toronto Pearson International Airport will record a daily high temperature, and this market settles on which Celsius range contains that figure as logged in Weather Underground's Daily Observations table. The 0% YES probability currently priced on Polymarket reflects the contract's structure: traders are pricing conditional tokens that resolve across discrete temperature bands, with no single outcome yet favoured. USDC collateral on Polygon backs these positions, and the settlement hinges on a specific data source—the granular observations feed rather than summary figures—which introduces technical precision into what appears as a straightforward weather event.

Toronto's August climate shows consistent patterns across recent decades. Historical data from Environment Canada indicates that mid-August highs in the city typically range between 24°C and 28°C, with extreme readings above 32°C occurring roughly once per decade. The 2021 heat dome pushed temperatures to 34°C in parts of Ontario, though Toronto proper remained slightly cooler. August 2023 saw highs near 27°C on comparable dates. These precedents suggest the market's probability distribution should cluster around the 25–29°C bands, with tail risk assigned to both cooler (below 20°C) and hotter (above 32°C) outcomes.

Weather forecasting accuracy for a specific date fourteen months ahead remains limited; seasonal outlooks from Environment and Climate Change Canada typically carry substantial uncertainty margins. Traders should monitor late-July 2026 medium-range forecasts and any anomalous atmospheric patterns (ridge positioning, humidity transport from the Atlantic) that emerge in the weeks preceding the settlement date. Real-time observational data from Pearson's automated weather station will be the final arbiter.

Methodology

This page reviews Highest temperature in Toronto on August 12? 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 PolyGram, which mirrors the Polymarket order book at 0% fees.

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.