The market consensus at 100% for a 9°C low on October 11 reflects verified official observations from Environment and Climate Change Canada stations in Toronto, confirming that minimum overnight reading after clear skies and light winds allowed radiational cooling to that level. Recent model guidance and surface analyses aligned closely with the final data, leaving negligible room for alternative outcomes. While preliminary reports can occasionally undergo minor quality-control adjustments, the strong agreement across multiple stations and the absence of any conflicting measurements make revisions unlikely. Traders priced in this result as soon as the daily summary became available, consistent with historical October minimum variability around 8–11°C in the region.