6 Answers

10 votes

Rain:

Tornadus / Tornadus-T: Good SAtk and STAB Hurricane, which never misses in the rain.
Thundurus-T: Massive SAtk and STAB Thunder, which never misses in the rain.
Jirachi: Good SAtk that can be boosted with Calm Mind, and gets Thunder.
Genesect: Great SAtk, and gets Thunder and get utilize Hidden Power [Water].
Dragonite: Good SAtk, can abuse Thunder, STAB Hurricane, and Rain boosted Surf. Can run a mixed set with Outrage.
Gyarados: Great Atk and can boost with Dragon Dance, and abuse STAB rain boosted Waterfall and abuse Moxie, turning it into a deadly Physical sweeper. It can abuse Thunder too! Just kidding. Don't abuse Thunder on Gyarados.
Gengar: While normally not a weather sweeper, it can utliize Thunder and Hex together quite nicely.
Jellicent: Also, not normally a Rain sweeper, but STAB Water Spout will hurt if it has full health. Slap a Choice Scarf to remedy the Speed.
Jolteon: Abuses Thunder and can take Electric moves for Rain teams.
Vaporeon: Normally used as a wall, Life Orb Hydro Pump or Surf coming from 110 base SAtk stat will hurt. Also can boost with Work Up.
Rotom-W: Abuses STAB Thunder and Hydro Pump, which are helped by the rain.
Toxicroak: Boosts with Bulk Up and Swords Dance, and heals itself with Dry Skin.
Tentacruel: Often used as a Special wall, it can use a Life Orb set of Giga Drain, Sludge Wave, Hydro Pump, Ice Beam is usable in the rain. Rain Dish will cover for Life Orb recoil.
Latios: Latios gets Surf and Thunder in the rain. Choice Specs is a big threat to lots of teams.
Volcarona: This fiery moth gets Hurricane, easily abused on a Quiver Dance set with it's monstrous SAtk stat.
Starmie: Starmie gets STAB Surf and Hydro Pump, as well as Thunder. It can also spin hazards that trouble rain teams. It can run a Specs or Scarf set with Trick.
Keldeo / Keldeo-R: Keldeo gets an insanely powerful Surf / Hydro Pump in the rain, and can boost with Calm Mind. It gets good coverage with Secret Sword.
Magnezone: It can abuse Thunder, as well as trapping Steels and setting up Charge beams on then behind Substitute.
Toxicroak: Can set up in the rain with Swords Dance and Bulk Up, gaining great recovery with Dry Skin and Black Sludge.
Cloyster: With Shell Smash and Skill Link, it can easily break through teams with STAB Icicle Spear and Rock Blast, as well as STAB Razor Shell.
Azumarill: Huge Power and Choice Band gives Azumarill 600+ Attack, and has rain boosted priority Aqua Jet, as well as Waterfall.
Empoleon: Usually a Special wall, it can use Agility to boost its Speed and abuse STAB Hydro Pump or Surf with its base 111 SAtk.
Froslass: Froslass gets a 200 base Water Weather Ball in the rain, turning it into a decent special rain sweeper.
Roserade: Also receives Weather Ball, and has Giga Drain and HP Ice to cover Pokemon that resist Weather Ball.
Kingdra: Has Swift Swim, and can go both Physical and Special. Usually used as a Dragon Dancer with Outrage and Waterfall, a combo only Shedinja and Empolen resist (I believe), or Choice Banded / Specs.
Raikou: Raikou also received Weather Ball and has Thunder.
Porygon-Z: Massive SAtk, and you will have trouble if it gets a boost and SAtk. It has Thunder to be abused, and also can have Adaptability Tri Attack, which hits ridiculously hard.
Sharpedo: Has great attack and boosts it's Speed via Speed boost, and can go mixed. Life Orb STAB Waterfall in the rain will hurt.
Zapdos: Has Thunder. Should've gotten Hurricane, IMO.
Nidoking / Nidoqueen: Gets Life Orb Sheer Force boosted Thunder, and will seriously hurt if unprepared.

Ok so Pb should be doing sun and rain so ill do Sand and Hail the best two wethers.

Hail
I love hail and its usually turned down and not many Pokemon benefit thats why most hail teams tend to be some form of stall.

Kyurem-130 base spatk stab Blizzard, need I say more. Dugtrio-traps and Kills other weather leads.frosslass-Snow Cloak and Stab blizzard. Raikou-Thunderbolt,Aura Sphere and Weather Ball (with 150 base power) Zapdos-Good coverage moves benefitting team Hariyama-Ok not a sweeper but as stated hail is more stall, it has thick fat to take fire attacks and then great coverage. Scizor-Good on any team. Heatran-Flash Fire absorbs fire attacks for ice Pokemon then hits hard. Mamoswine-Good attack and benefitting ability. Latios-Ability to take out all wether leads and Blizzard is usable.

Ok I havent listed many ice Pokemon but ive been playing with hail for ages and these are your best sweepers.

Sand

Landorus-Sand Force and great coverage.Rotom-W-Volt Turn is almost seen on all sand teams and Rotom provides great synergy. Latios-Great sweeping capabilities. Excadrill-Your best sand sweeper in ubers. Garchomp-Great sand sweeper in Ubers. Sandlash-Sand Rush and stab moves. Scizor-Volt-turn and no damage plus priority.Starmie-Coverage and spinner. Thunderus-T-great weather counter. Dugtrio-Trapper, sand force and decent coverage. gyarados-Great in sand easy set up and will wreck any opposing team. Metagross-No damage, good synergy(usually) and coverage. Alakazam-Magic Guard prevents no sand or life orb damage this also works in hail.

Ok me and Mike said no massive descriptions we would be here all night or day what every zone your in.
These are all standard Pokemon and ones used by me successfully.

I use Charizard as a special sweeper in Ubers, and as long as the SUN is strong and you time his switch-in properly, he can be devastating with his special attack reaching upto 712 ! It can even take out those pokemon in one hit who are "not very effective" to flamethrower!

Perhaps Cryogonal would do well here with its SolarBeam? I mean, it's super totally omega-weak to fire, but it's got incredible Sp. Def. Runs a good Specs set, and can catch foes off guard. "An Ice Poke in a SUN team!?"

Solarbeam is usually a bad move in sun because of the immense presence of sand and rain in OU and Ninetales' SR weakness it will be rendered useless should you lose the weather war, which is not a hard thing to do. I can see running Solarbeam on Sunny Day Ninetales but not much else Tbh. But I like your idea :)

Rain Part II:

Rain:

Crawdaunt: STAB Adaptability Crabhammer in the Rain: 360 Base Power. Enough said.
Galvantula: Has a good SAtk to abuses Thunder with.
Feraligatr: Boosts with Dragon Dance and can potentially screw over teams with Life Orb Waterfall. Also has Ice Punch and Earthquake to stop Grass, Water, and Dragon types from surviving.
Kabutops: Has Swift Swim and boosts with Swords Dance. Outspeeds loads of stuff and hits hard with Waterfall, Stone Edge, X-Scissor.
Omastar: Also has Swift Swim and boosts with Shell Smash. Has Ice Beam and Hidden Power to round out coverage.
Manectric: Abuses Thunder and takes Electric moves for the team.
Poliwrath: Can abuse Swift Swim, and boosts with Bulk Up and hits with Waterfall and Drain Punch. Like a Physical Keldeo.
Qwilfish: Qwilfish has Swift Swim, and can run a decent Swords Dance set with Waterfall, Posion Jab, Swords Dance, and Return.
Rotom-C: Abuses Thunder can nails Gastrodon, which gives Rain teams some trouble.
Articuno: Can abuse Hurricane quite well. Also can carry Water Pulse, which is rain boosted.
Basculin / Basulin-B: Abuses Aqua Jet and Waterfall with Adaptability.
Carracosta: Has Swift Swim, and can use Shell Smash to use Aqua Jet, Waterfall, Ice Beam, Stone Edge, Earthquake, and more with.
Gorebyss: Has Swift Swim, and sweeps very well after Shell Smash. Surf, HP Grass, and Ice Beam hits everything neutral except Shedinja.
Huntail: Has Swift Swim, and goes physical with Shell Smash.
Pikachu / Raichu: Abuses Thunder and takes Electric moves. Pikachu has more power with Light Ball.
Swanna: Has STAB Hydro Pump and Hurricane, which are both useful in the Rain.
Wailord: Can run a Choice Scarf set with Water Spout, which will HURT under the rain. It will have 450 base power after all boosts.
Lapras: Can do a Rest boosting set with Dragon Dance and Waterfall. Has Ice Shard for priority. Hydration cures Sleep status in rain, letting an easy setup.
Whiscash: Can do a Rest boosting set with Dragon Dance, Earthquake and Waterfall. Hydration cures Sleep status in rain, letting an easy setup.

I love using him. He isn't hard to use, and is quite effective. Thunder punch is great for jellicents trying to wall you. Plus most of them carry scald, which won't burn you and gets a 50% decrease in the sun.