A lot of species are just migrating through to their breeding areas and don't stay. Some raptors do not migrate and are here year-round. Once in awhile you'll get a bird(s) that are out of their range, blown off course, or perhaps displaced due to lack of desired prey. For example, this happens with snowy owls when lemming populations in the tundra crash. We had sightings of them here last winter.
Red tails are year-round in your area. It's also breeding season & this one of yours may have a nest nearby which is why you may be seeing it so often.
