Damage proc in Lightning Storm
That's right. Each lightning strike has a chance to proc.
Just to be clear, the proc checks individually for each of the up to 5 targets Lightning Storm can hit. So it doesn't check per strike, but rather per target (which is what Garent meant, but I thought I would spell it out to avoid confusion). This is also the way hold and stun procs work in LS as well.
Draggynn on Virtue: lvl 50 Storm/Psi, 1389 badges
Draggynn's Guide to Storm Summoning(Gale-Tornado, updated 6/25/2011)
Avatar by Wassy full reference here
This is great news, thank you!
Does a dmg proc function if its in Lightning Storm? I.E every time it strikes there is a 20% chance for the mob to take more damage? Sometimes these procs work strangely with pets.