Just a quick question for those operating big jets - if you should see bad wx on your radar, how do you go around it? I mean, the FMC has all your waypoints set up and the course between each one will be flown by the autopilot. Do you have to disengage the autopilot to make a turn around it? If you are over somewhere where HF radio is your only contact with ATC, do you have to tell them you're going around the bad wx or do you just do it and re-establish your route to the next waypoint when you've safely got around it? Typically how much do you have to turn to avoid it, is it just a few degrees or a whacking great course change?