Like the guy after you mentioned, Abomasnow is BL so you're going to have to set Hail up manually. Even then, though...Glaceon's STAB'd Blizzards/IB's are certainly powerful, but there are several 4x Ice resists in UU that'll just laugh (252 HP, no sp def Lapras takes 13.92% - 16.51% from Blizzard and 25.00% - 29.48% from Shadow Ball, Walrein has defensive stats very similar to Lapras, Dewgong has lower defenses than either of them but still takes little damage) and won't take a whole lot more from it's other attacks. Even if you don't have a 4x Ice resist, there are a lot of things that can survive a hit or two from it and KO it back (Ice has plenty of weaknesses and Glaceon is pretty slow).
Why would you BP Nasty Plot to Glaceon in the first place? Low speed, awful movepool, and it's not particularly durable either.
I take issue with Glaceon for UU.
First, it is faster than Lapras/Walrein anyway, and with 65/110/90 Defenses, it won't win wall of the year, but Walrein and Lapras' STAB water attacks still won't take it out. Since it will be seeing fewer rock or steel types in UU, it can probably afford to go with HP Grass or HP Electric instead of HP Fighting.
Do remember that Glaceon has a godly 130 Special Attack Stat and 3 special moves, one of which hammers the Psychics in UU, and the other which obliterates nearly anything that doesn't resist it. Unlike Flareon and Glaceon which also have 130 attacks, Glaceon can actually attack without that much redundant coverage.
Modest Scarf Glaceon can hit 343 speed, which is enough to beat +Speed Manectric and Scyther. Modest Specs Glaceon is working off of 591 SA, and there's no Blissey or Snorlax around to eat all of its attacks.
HP Fighting gives you coverage for the 8x Ice resists, as well as Lapras, Aggron, Bastiodon, Probopass, and Mawile.
HP Grass gives you coverage for all water switchins, especially Quags and Gastrodon. It still techincally deals less than Ice Beam on Rock/Steels. HP Grass is superior to HP Electric in nearly every concievable way in UU. The only thing HP Elec hits harder than HP Grass or Ice Beam is Mantine.
Max SA Modest Scarf Glaceon Ice Beam on 252 HP Aggron:
37-44%
Max SA Modest LO Glaceon Ice Beam on 252 HP Aggron:
49-57%
Shaky 2HKO.
Max SA Modest Specs Glaceon Ice Beam on 252 HP Aggron:
56-66%.
2HKO.
HP Fighting is a OHKO.
252 HP/148 Impish Bastiodon:
Max SA Scarf:
18-21%
Max SA LO:
23-27%
Max SA Specs:
27-32%
HP Fighting:
Max SA Scarf:
71-84%
Max SA Life Orb:
93-109%
Max SA Specs:
107-125%
252 HP Modest Probopass:
Scarf Ice Beam:
18-22%
LO Ice Beam:
24-28%
Specs Ice Beam:
28-33%
Scarf HP Fite:
74-87%
LO HP Fite:
96-113%
Specs HP Fite:
111-131%
Super-Effective HP on
252 HP Walrein (Lapras takes similar, but slightly less damage):
Scarf:
43-51%
LO:
56-66%
2HKO. (On Lapras, 49-58%)
Specs:
65-77%
Shadow Ball on 252 HP Poliwrath:
Scarf:
27-32%
LO:
36-42%
Specs:
41-48%
HP Grass on 252 HP Poliwrath:
Scarf:
48-57%
Likely 2HKO.
LO:
62-73%
Specs:
72-85%
Conclusion: Since Glaceon can in most scenarios one or two hit KO most of the opponents that would switch into Ice Beam with a proper Hidden Power, and since Glaceon will inevitably be faster than any remotely defensive variant of these switchins, Glaceon has no true counters in UU and therefore should be BL unless there is a ban on the use of Hidden Power.