Polis, nowhere is really safe but you absolutely want to be off the summit and the ridge between the summit and Trail Crest if there's any chance of lightning. That's where the heaviest lightning activity usually takes place.
If all else fails and you're stuck in an exposed or dangerous area in a lightning storm, get far away from any metal objects (trekking poles) and squat on your pack to reduce your contact with the rock (an overlooked conductor of electricity). Do not seek shelter under a rock overhang or ledge, despite the sense of comfort this might give - again, rock conducts quite well. Same reason you don't want to be in the summit hut. Well, that, and the metal roof!
