I’m trying to gauge my chances at UW as an out of state student (I’m from Texas) because I know that the vast majority of the student body is from Washington state.
Stats: 1570 SAT (790M, 780RW) (Probably low adversity score). 4.0 UW GPA, 1/40 students (I know, small class). 770 Biology E subject test, retaking math II in August. 10 AP’s, only know how I did on Euro (5) but I think I’ll get mostly 5’s with a 4 or two.
EC’s: Debate- 500+ tournament hours between 40+ tournaments. Speech captain my junior year and Public Forum Debate Captain next year. Qualified for my state’s (TX) state tournament twice, qualified for the national tournament twice. Academic All American (750+ speech and debate points, awarded to 0.5% of debaters each year. First student from my school to qualify for the Tournament of Champions. Nationally ranked Public Forum Debate team. Sports- member of varsity track and cross country teams. Leadership- Honor Council member all 4 years and Honor Council Chair senior year, student senator junior and senior years, NHS Vice President senior year, Varsity Cross Country team captain, peer advisor, admissions team representative. Community service- writing center tutor (reviewed writing of my peers and made suggestions and edits to essays), built bird and bat nesting boxes for my school’s forest to support animal populations, trying to volunteer at my local state park, food bank, pet shelter. Probably around 80 hours total. Other- Attended Sustainable Summer program at Dartmouth where I learned about environmentally friendly business practices and environmental policy.
Essays and rec.s: Haven’t done essays yet but I’m a strong writer and I think they would be pretty good. I have an interesting story being a Jewish vegetarian in the Bible Belt of BBQ-loving East Texas. Teacher and counselor recommendations should be very good.
I honestly have no clue whatsoever how selective UW is for OOS students, so hopefully somebody might be able to help me out 
You are a very strong student and I would think your chances for acceptance would be good. The toughest part of UW is getting accepted to the major of your choice. We have friends who were accepted to the University but not the Computer Science, Engineering or Business schools. Many of them chose to attend schools elsewhere. I really think you just have to apply and see what happens! Congratulations on a successful high school career. We are former Dallas suburb residents and love living in Washington State now.
You look like a very strong candidate and should be admitted. Freshman admit to the Foster Business School is a little easier than computer science or engineering school. Hopefully, you can afford the yearly cost of a little over 50K per year which includes out of state tuition. Your in state flagship public school, UT Austin, is a lot cheaper pricewise and has similar rankings to UW Seattle.
You seem like a strong candidate. Note: you should also be a good OOS candidate for the Purple and Gold scholarship which is as much as 8K per year which can help with the high cost of OOS tuition.
Only real downsides to UW is the weather (rainy/overcast) during most of the school year and possible overcrowding.