4 encounters you'll only get if you're a 90's kid.

Ok not really.

Actually as winter is wrapping up, I thought I'd list some encounter ideas on that theme, before it's too late.

Next time your party is wandering through the Forbidden Ice Crags and the druid/ranger keeps asking if you're in the woods because their favored terrain is the woods but you've told them like a million times that you're on the tundra but then you describe some stunted trees in your flavor text and they decide that's basically a woods so they should get bonuses, they might be ready for one of these.

dammit olaf get the hell out of here

Roll 1d4, or 2d4 and they're fighting each other when you arrive
1.  Barbarians on dogsleds.  The barbarians are armed with obviously stolen lances, and all the adventurers are slowed due to the heavy snow unless they're on dog sled or wearing snowshoes or whatever. The sled gets slower for each dog they kill, until the barbarians just jump out and release the hounds (1 action) once they're pretty slowed.  The sled dogs fight as wolves, which actually makes these enemies MORE dangerous as they get hurt, which is great.
2. Avalanche Elemental While you're heading up a mountain or slope, your party gets slammed by an avalanche. Pretty bad, but hopefully you can dig everyone out and look for shelter.  Then you notice that the snow is heading back up the mountain.  Right above you. Uh oh.  Show your players a clear gradient on a battle map or i guess just describe it, the avalanche elementals can only attack people that are down slope from them.  They pack a wallop but move slowly, and sometimes have to spend a few turns positioning.  Your players should be terrified of getting caught.      
3. Mountaineer Zombies.  These zombies rise up out of the snow, dressed in anachronistic mountaineering clothing, hair all falling out and skin black with frostbite.  They look kind of like these guys

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They're all tied together still and are obviously located right near some sharp crags and drops with scary rocks at the bottom.  If you push them off, watch out you don't get caught by the ropes.  Although they don't seem to want to fight at first, they just seem desperate for the PCs to set up camp and a fire.  Wait are we sure these guys are zombies? (some are though, and remember they're all tied together)

 4. Gnomish ??? and Goblins.  Some sort of old gnomish machine lies abandoned in the snow.  2d10+3 goblins are crawling all over it, ripping it apart, putting it back together (kind of) and loudly arguing.  The goblins look ridiculous with thick coats and big furry hats.  They'll aggressively defend their find, and they've got it working again.  Well, they've got the flamethrower part working.