Highest temperature in Toronto on August 12?

Platform comparison

Market context

On 12 August 2026, Toronto's highest temperature will fall within one of several defined ranges. A YES share in any given range pays out if that range contains the actual peak temperature recorded at Toronto Pearson International Airport's weather station. A NO share pays out if the temperature falls outside that range. The resolution hinges on the Daily Observations table in Weather Underground's historical data, which captures sub-hourly readings rather than the rounded summary figures many casual weather users consult. This distinction matters: the Daily Observations table often records slightly different extremes than the Day High & Low summary section.

Toronto's August climate is relatively stable year-on-year. Historical data from Environment and Climate Change Canada shows that mid-August highs typically range between 24 and 28 degrees Celsius, with extremes rarely exceeding 32°C or falling below 20°C. The 0% probability assigned to the current market likely reflects either the market's early stage or a specific temperature threshold that sits well outside the normal August distribution. August 2024 saw Toronto peak at 27°C on the 12th; August 2023 reached 26°C on the same date.

Traders should monitor long-range forecasts as August 2026 approaches, though such predictions remain unreliable beyond two weeks. Urban heat island effects around the airport and any unusual atmospheric patterns—such as early autumn cooling or a heat dome—would shift outcomes. The settlement window closes at midday UTC on 12 August, meaning North American traders have until early morning to adjust positions based on overnight forecasts.

Methodology

We track Highest temperature in Toronto on August 12? 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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

UK Frequently Asked Questions

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.