This is a very interesting report. If you have details on this
sighting, you should submit them. A number of "less common" warblers
are,as you imply, in fact more likely in Vermont at this time of year
than a Yellow (for example, Nashville, Tennessee and Orange-crowned).
> Yesterday at Dead Creek my son Spencer and a Mascoma Audubon group
> found a Yellow Warbler.
> According to e-Bird, this is the latest observation of this species in
> He will post a full list tonight.
> Doug Hardy, Norwich