Official Environment and Climate Change Canada observations at Toronto Pearson International Airport confirm the highest temperature on April 25, 2026, reached exactly 10°C during the afternoon, driving near-unanimous trader consensus (100% implied probability) for this outcome. A persistent cool upper-level trough over southern Ontario suppressed highs under cloudy skies with light rain and drizzle, aligning with pre-event forecasts near 10°C and below the historical April average of 11–12°C. Model consensus from NOAA and Canadian ensembles accurately captured these conditions, reflecting low uncertainty in post-event verification. Realistic challenges include rare data revisions or station-specific measurement discrepancies on Wunderground (the resolution source), though official records provide strong evidentiary support.