According to Spanish radio station Cadena SER, Alvaro Morata's agent is in Madrid today to work with Real Madrid to negotiate a return to the club from Juventus, where he moved in summer of 2014. Real have a much-discussed buy-back clause in the transfer deal which it appears they are planning to execute during this summer's transfer window.
The buy-back clause is reportedly €30 million, meaning Real Madrid could buy Morata again and then flip him immediately to another team. Cadena SER claims Arsenal are "crazy" to get him, which I assume refers to a level of enthusiasm rather than being a claim that the move would be a bad one. The radio station says Morata and his people are pushing for a move to the Premier League, so it's possible that checks out.
Evidently an Instagram post was spotted depicting Morata with some Juve teammates and a cake that said "Adios Amigo 9," so it does appear that the player's on his way out at the Italian club. What happens after that is yet to be determined, but it's a first step, I suppose. I'm still skeptical that Arsenal will be able to sign the player, but stranger things have happened.