While playing against the Zerg, I used my 3 teams of Dragoons followed by a full team of High Templars to destroy an enemy Zerg base. The goons took care of all of the colonies while the High Templars went right for the Drones and the economy. All 12 of the High Templars put a psionic storm on the drones which were at the time right at the Hatchery and not only did all of the Drones died but so did the Hatchery. I didn't know that psionic storm did any damage to buildings but it completely destroyed it in seconds flat. I even checked on the StarCraft Wikia and this is what it said

"Inflicts 112 damage to all units within a certain area over seven seconds. The storm does not harm structures or units within bunkers. Units may move out from under the storm thus limiting the damage they take. It is most effective against groups of weaker units clustered together. A few Psionic Storms are sometimes even enough to turn back large fleets of powerful vessels such as battlecruisers or carriers or a large attack force of mixed units."
~Psionic Storm on Wikia

Anyone know why it destroyed the building if it wasn't supposed to? I should have saved the replay but I forgot about it...

I'm sure it didn't. Replay or it didn't happen.

The Hatchery was probably low on HP and some Dragoon you didn't notice killed it.

Also, psionic storms don't stack, so you really shouldn't be telling 12 of them to storm the same location...

Not to mention you shouldn't be marching 12 templars with 3 goons as protection.

He clearly said 'teams'.

if them templar are dark you can suprise them making um think its a goon scout?

Psionic Storm deals 14 armor-ignoring damage 8 times (112 total damage), with a splash of 48. It does not harm buildings nor does the damage stack.

My bad.

What do you mean by splash? If a unit is at the edge of Psionic Storm next to another outside of the storm, will both be hit...?

It's simply baseDamage * numOverlays * isUnitUnderGraphic. Armor is completely ignored. It will always do full damage.
It does not damage buildings.

The base damage is 16.

I believe that one of the unknown upgrades increases the damage.
I don't know which, and I don't know by how much per up, I just know it happens.

unknown upgrade 60, increases damage by 1 per upgrade for each damage cycle.

60?
I thought there was only like 10...

UnknownUpgrade60 is what anything that doesn't have an upgrade is set to.

Oh really? I was under the impression that psi storms did stack, but units had a limit as to how many they could be affected by (max stack).

Good to know.