I also want to gently point out that it is very feasible to finish up your BA/BS in WA and then move to the South to get a job, go to grad school, etc.
You can join the Junior League there, as well, and be involved with sorority alumnae life if you join a sorority in undergrad.
I went to school in FL and fit in just fine with my AA and the Alum Panhellenic in my area of Texas quite well. Just something to think about since you have a year before you would transfer to a 4-year school.
If you are really interested in sorority membership, rushing at the majority of schools in the "Deep South" or an SEC school is not going to be a very pleasant experience for the vast majority of upperclassmen. Just putting it out there. I'm sure you will make the decision that best fits you and your needs.