Nope. Most of the zone events can't be triggered. Just have to wait for it to happen. Make sure you have the 'Hero Zone Events' channel in your chat window so it will tell you when a raid starts.
Paragon City Search And Rescue
The Mentor Project
Guess I'm at the mercy of the clock then. Thanks for the reply 
Does anyone know if there's a trigger to get the trolls in skyway to start raving?