In Central and Southwestern Ontario, which specific week in October is the rough deadline for seeing autumn foliage before it ceases changing colour? Unpredictability in rate of foliage change nullifies providing specific dates as the deadline.
You can check fall colours on websites that show maps or give text reports:
- https://www.ontariotravel.net/publications/fallcolourreport.pdf is text only, updated once a week. Currently says "Many long-time Algonquin Park fall colour watchers are predicting the peak Sugar Maple colour to be later than the September 27 average of the past 40 years."
- http://ontarioparks.com/fallcolour is supposed to have a map according to other people's screen shots, but it doesn't work for me. It has text for sure.
I like to do my leaf peeping Thanksgiving weekend which would be Oct 10/11/12 this year. I suggest picking a weekend and then you just vary how far north you go.