Morwal is a disease like condition that happens to a wolfblood when they have suffered great loss and/or pain, usually from recent events. The wolfblood will become highly aggressive for the following full moon. Jana describes it as if a whole other wolf has taken over, and that the wolfblood will not be able to control it.
Jana gets the morwal in Series 3, after she comes to believe that she no longer belongs to a pack, and that she could never be a good leader. She tries to find a new pack in the Three K's, and at first, it works in her favour. They are nice to her for a while , however, Kay starts to believe that Jana is trying to steal Tom away from her. She takes action, and tries to stop Jana. Kay, Kara, and Jimi lock her in the Kitchen at Bradlington High. Shannon and Tom calm her down before she wolfs out, and Jana soon realised she still belonged to a pack in Stoneybridge.
In Series 4, Carrie Black is tracked down by Jana after Segolia make an attempt to capture and captivate her. Jana offers her to get away from Segolia before they catch her, as Carrie has the morwal, and Jana has a duty as Alpha to keep her away from people before she hurts anyone.