Highest temperature in Toronto on August 12?

Platform comparison

Market context

On 12 August 2026, Toronto's highest temperature will be recorded at Pearson International Airport and measured against defined Celsius ranges. The crowd currently assigns zero probability to the YES outcome, suggesting either extreme confidence in a specific temperature band or genuine uncertainty about which range will resolve as correct. Settlement hinges on Weather Underground's Daily Observations table, the authoritative source for this market, rather than summary figures that occasionally diverge from granular station data.

Toronto's August climate is reliably warm but not extreme by North American standards. Historical August highs at Pearson typically range between 24–27°C, with temperatures exceeding 30°C occurring roughly once every three to five years during heat waves. The 0% probability reading indicates the crowd has already committed to a particular range or ranges, leaving little room for contrarian positioning unless traders believe the consensus has mispriced the likelihood of an outlier event—either an unusually cool day driven by lake-effect moderation or a rare heat dome pushing well above seasonal norms.

Traders should monitor Environment and Climate Change Canada's seasonal forecasts and any heat warnings issued in early August 2026, as these typically signal when temperatures might deviate significantly from the 25–27°C median. The specific resolution mechanics—reliance on Daily Observations rather than Day High & Low summaries—matter operationally; discrepancies between the two sources have historically favoured the granular data. With settlement at noon UTC on 12 August, the market closes before the day's peak heating, so the highest recorded temperature may reflect morning or early-afternoon readings rather than late-afternoon peaks.

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 Who Will Win 2026. 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'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.

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.

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.