I really want my parents to select a city that's warm and on the California coast.
Why do you want to push them to select a city that's warm?
I want to move to a warm area that doesn't experience the change of seasons.
I understand you have preference for warm weather, but it's wrong to make your parents make a decision only based on your needs. You can voice your opinion but they should not be obligated to make a choice based on your desires. The choice should be based on what works best for everyone involved.
What's wrong with that? I just need them to get a place where I can live. I don't want to get my own place.
You should your own place where you want to be that is not where your parents live. It is good to be independent when you are grown up.