Augur Stack Exchange has been closed down four days ago, according to its Area 51 page. Yet, it's still visible in SEDE. I was wondering how long it would be kept; sites which have been closed for longer (e.g. Startups and Personal Productivity) are not available anymore.
Incidentally, while doing some research for this question I'd expected Arabic Stack Exchange to appear in the list of databases since many of my cross-site queries make an exception for this site. Apparently, that is no longer necessary ...
While we automatically add new sites to public SEDE, the weekly refresh process doesn't remove closed sites. That means they are removed when we remember to do it.
I went ahead and manually removed the site from public SEDE and it shouldn't be included any longer when we refresh the SEDE each week. I've also created a To Do item for myself, to update the process to automatically drop databases and sites from the weekly refresh when they are permanently closed.