joining a sorority

I think you shouldn't even rush truth be told because if the only reason you want to rush is because you want to be in a top house then you don't even deserve to be in the Greek system.
HOWEVER
if you actually want to be part of the Greek system because if the sisterhood that comes with then you will most likely be In a house that accepts and loves you. Which means can most likely be in a house so you should definitely rush still.

Yeah I completely agree with the person above, there is so much more to the Greek system than the tiers. If you are really interested in joining this year take a look at Phi Mu, they are starting recruitment in January.

Don't Rush if you just want to be in a top house. That's the wrong reason to go into it. You should look at houses doing COB there are great ones still taking members. Or like the person above said look into the new chapter that is opening up but first reconsider your reasons for going Greek.

If you think Greek Life is represented by this website you are in for a big surprise, I would recommend talking to people in the actual Greek community and finding out what it really is like. You seem like you lack the confidence to do anything outside the norm, "I haven't heard of anyone doing it though."
I hope I am not being too harsh but it sounds like you just want to be in a house for superficial purposes not because a sisterhood is actually something you are interested in. If you want to join a sorority, the website you should be on is uwgreeks not greekrank. The people you should be reaching out to should be the recruitment chairs not anonymous people who may or may not even be students at UW. It's incredible frustrating to read posts by people who are ill-informed when all the information is easily available and accessible.

I know a junior who rushed this year, but I know it was pretty difficult for her. She ended up in a good house, but her options were much more limited than if she rushed as a freshman. Still try rushing if you have a good GPA and extracurriculars to make you stand out. Honestly, looks help a lot too.