Yes we are still in the midst of raptor migration season, which generally happens from September to mid November. I was at the Rosetta McClain raptor watch yesterday where we had over 200 raptors and 11 species moving through. It is likely that your sister observed a "kettle" of Turkey Vultures rising up on thermals before "streaming" out and continuing along their chosen path. Sometimes other raptors will be mixed in as they take advantage of the same thermals that help them on their way. On a strong north/west wind day the birds are pushed down to the lake where they then follow the shoreline west until they reach a place where they can cross over. Depending on wind conditions, some of these birds will fly over the city further north of the shoreline. We often suspect some of the birds that we see are continuing past Rosetta and along Kingston Rd, Danforth, and Bloor; but it sounds like yesterday they were following Gerrard instead.
If you or your sister are interested in learning more, you will find an excellent guide to raptor watching here:
http://www.ofo.ca/site/page/view/articles.hawkwatchingIf you would like to visit a raptor watch there are several in Ontario and two here in Toronto: The High Park watch conducted on the hill behind the Grenadier restaurant, and the Rosetta McClain watch in Scarborough
https://raptorwatch.blogspot.ca/ The best days to visit are North or North/West wind days!
