It is very hard to say when we will see peak foliage as it is related both to the length of daylight (pretty predictable) and temperatures (not so predictable).  If we get a sudden turn to colder temperatures, the leaves could start to change quite quickly.  Typically we would expect to see great foliage peaking in October and into November but within that range it can vary a lot from year to year.

Courtesy of NYBG Plant Information Service