Latest meteorological guidance from Environment Canada points to a sunny high near 23°C in Toronto on May 17 under a strengthening ridge of high pressure and southwesterly flow that advects milder air northward. Clear skies should maximize solar insolation, though modest afternoon wind speeds and boundary-layer mixing introduce a narrow uncertainty band centered on 22–24°C. Trader consensus, reflected in the closely matched implied probabilities for those three outcomes, mirrors the spread across ensemble guidance, where small shifts in cloud timing or wind could tip the daily maximum by one degree. Historical May climatology supports this range, with highs typically peaking in the early afternoon before any seabreeze influence. Updated model runs tomorrow morning represent the next key data point that could reprice the market.