Not many schools have actual dorms. Many many schools help you arrange boarding.
There are smaller schools in places like Rochester NY, Richmond and Norfolk VA, etc which tend to take in girls who need a change of pace. I know people who went to all three (community residents, not boarders) and I believe that the girls board with families.
If you don’t mind Chabad, I’m pretty sure that a bunch of their schools welcome girls from out of area and I think that many have dorms (one of my sem teachers was once a dorm counselor at one of them).
BY Denver has a dorm. YGW takes people from out of the area but I don’t believe has dorms any longer.
Schools all over the tristate area will probably help you find boarding families, or you can look out on your own. But very few schools have their own dorms. I know several girls who took that route (attending a standard community school while boarding with a local family) and were very successful- this gives you the opportunity to look for schools solely as far as how they fit your needs without needing to worry about their dorming situation.