Brief report:
Hiked with awagher. Started at Bumpass Hell trailhead as that's how far the road was open to on 5/27/05. Up and down in about 3 hours. We literally had to run down from the summit to flee the thunderstorm & lightning (my ice axe was humming due to the static build up). We headed next to Mt. McLoughlin.
Additional info about climbing Lassen Peak can be found here.