Lightning Storm

Evocation [Lightning]

Level: Sor/Wiz 9

Components: V,S

Casting Time: 1 Action

Range: Long (400 ft. +20 ft./level)

Area: 100 ft. Radius

Duration:Instantanious

Saving Throw: Reflex half

Spell Resistance: Yes 

You summon forth a powerful lightning storm. The storm 
covers a 100 ft radius. Each round the spells area is 
assaulted by lightning bolts dealing 5d6 dmg to every 
creature caught inside per round so long as you 
concentrate and 2 rounds after you stop concentrating.
Reflex Save for half.