Official observations from Environment and Climate Change Canada at Toronto Pearson International Airport recorded a daily maximum of 24°C on May 31, 2026, driving the near-certain market consensus on that outcome. A stable high-pressure ridge delivered sunny skies and limited afternoon mixing, pushing temperatures above the late-May climatological normal of roughly 21°C. Ensemble forecast guidance had shown tight clustering around 23–24°C with minimal spread, aligning directly with the final verified reading. Resolution depends solely on the station’s official maximum; an unlikely post-publication data revision or instrument recalibration could theoretically alter the outcome, though historical precedent indicates such changes are rare once initial reports are issued.