Highest temperature in Toronto on June 25?

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Active sub-markets

Market context

The 0% crowd-implied probability for a high-temperature range on 25 June 2026 at Toronto Pearson reflects today’s actual conditions: thundery showers, a high of just 21°C, and 80% rain probability, which starkly contrasts with the scorching 35.8°C recorded at the same station on 25 June 2024. That recent heat event, the city’s hottest in nearly a decade since July 2016, temporarily pushed June into record territory, yet today’s cool, wet start has erased any expectation of similar extremes for this year’s settlement window[3][4].

Historically, late June at Pearson sits in the transition zone between mild spring and peak summer heat, with July averaging 80°F (26.7°C) as the hottest month, while June 25 has only once since 1938 seen a low of 22.9°C, indicating that extreme highs are rare but not impossible on this date[1][9]. The current 0% probability aligns with today’s forecast of 19°C overnight lows and persistent cloud cover, suggesting traders should treat this as a near-certain miss unless a sudden heatwave develops.

Traders must monitor Environment Canada’s heat advisory updates and the National Weather Service’s real-time data for CYYZ, as any shift toward dry, sunny conditions with temperatures exceeding 30°C would invalidate the current consensus[6][7]. A recent CBC report confirmed that heat warnings can persist for days when humidex values reach 42–46, so the next 24–48 hours of forecast revisions will be the critical catalyst for this market[6].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Toronto on June 25? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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

Is this market available outside the US?

Prediction Today is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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.

What does it cost to trade on Prediction Today?

Zero. Prediction Today routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

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.