I have 3 chars, with the first one I finished all quests, sides, gluilds and miscs (almost) and cleared all clearable places, I never encountered a single storm atronach (idk if I'm spelling it right) in the wild nor a mage ever summoned one against me.
The only ones I've seen are those in the wabbajack quest and those you can summon.
Sup with that? It's just me?

I've had enemies summon them against me numerous times. My Nord warrior is obviously 50% resistant to cold, but for some reason shock attacks seem to hit him harder than fire attacks, and I've never really figured out why.

they usually summon the ice one against me...

Probably having scaling issues, i am also having scaling issues... Im lvl 40 yet enemies feel like they are still around lv30-...

It's likely a question of level. Fire atronachs at lower levels, then ice, then storm.

I've had a few summoned against me from I believe were Draugr or possibly Conjurors. If you give a staff of Summon (Name) Atronach to your follows they'll use them quite regularly. It's better than you getting it out all the the time and if your already a conjuror then you technically get 4 NPC allies at any one time although you can still get more.

I'm lvl 59 and playing on master with my first char...

Huh. That is odd then. I'm like level 43 or 44 and I just started seeing storm atronachs in the last couple days. I suppose some mages are specifically fire, ice or storm mages, and will summon their respective atronachs regardless of the PC's level...

yeah, you probably right...gotta find a storm mage...

btw, so I guess none in the wild right?

Can't say I've seen any described as storm mages, myself. I've mostly seen them summoned by Thalmor justiciars and mages. I suppose that there might be storm mages, but to be honest, now that I think about it, I'm not even sure if the fire mages summoned fire atronachs and the ice mages summoned frost atronachs. They might have just used destruction rather than summoning. Not sure about that.

Who have you seen summoning the other atronachs? Fire and frost mages, or just summoners, or what?

Thalmor mages usually cast them when you come across them in the wild, you have to provoke them through speech to kill without a bounty.

Which I always do. "I worship whoever I want" does wonders at getting those idiots to stick their faces in a grinder (my axe) without getting me in any legal trouble.

I don't know if the Thalmor in any city - Solitude, I suppose - do anything quite so stupid, however.

Same haha, I can't not kill them, even with my altmer character. I wouldn't even say my character worships talos, I just do it for those who do.

theres's storm mages too, found some in dungeons, probably never outside, but they never summoned one
I'll try find some more and wait until they do.

Storm atronachs and Electromancers are probably the worst enemies you could face if you don't have high magic or shock resists. They can almost always hit you even far away. If you rely on magicka, it's even worse. That's why a lot of people have problems with Morokei.

I've had several thrown against me more in the wild than anywhere else

Well, I guess the reason they give me so much trouble is because of the nature of the spell, not because shock hurts me more than flame. It's because of the fact that the shock spells are instant-zap spells, while the flame spells are a short-range gout of flame and a fireball. The fireball takes time and is essentially a missile, so it's almost as easy to evade as the ice spike spell. The fireball doesn't have to hit me, but it does have to hit near me to damage me. The shock spells all they have to do is point their crosshairs on me and ZZZAAAAAP.

In short, you can't evade shock spells like fire and frost.