Hurricane reads:
Hurricane deals X damage to each creature with flying and each player.
Does it deal damage to creatures that cannot be targeted?
Hurricane reads:
Hurricane deals X damage to each creature with flying and each player.
Does it deal damage to creatures that cannot be targeted?
Hurricane doesn't really "Target" per se, it just affects each creature.
So yes, as long as the creatures have flying, it will deal damage to them even if they are untargetable.
I think that as long as the card doesn't say "target creature" or "target player", it will be able to affect creatures or players even if they cannot be targetted. This card says "each" creature and "each" player.