Does every raid have a story mode going forward?

I remember at the end of TWW doing a raid with Xal'atath and killing Dimensius. I hardly ever group due to time contraints so I loved being able to see the cut scenes and story. Will we get that from now on. Also I just dinged 90 a few days ago so which raid is the first one? A week or two ago there was some big spoilers in the ending cinematic and I have avoided all spoilers so far thinking I'll get to see it with my own eyes. Can you manually turn on story mode? I believe the Dimensius one I went in was part of a quest and I don't know if I've picked up a quest line that will lead me to that raid.