Okay, I don't put in that really discriptive stuff and pictures and what-not. And I'm terrible at descibing things, so bear with me.

Groudon @Life Orb
Drought
Adamant 112HP / 252Atk / 136Spe
-Rock Polish
-Earthquake
-Stone Edge
-Dragon Claw

I start off with Groudon to set up Sunny Day (duh). I Rock Polish while they set up Stealth Rocks or something. Then I take out whatever I can until Groudon faints. Or I may switch out if I feel he may be needed later.

Ho-oh @Life Orb
Pressure
Adamant 224HP / 252Atk / 32Spe
-Sacred Fire
-Brave Bird
-Earthquake
-Roost

Sacred Fire in the sun will do a ton of damage. It also has a great chance for burn (50%). I have a Life Orb to boost Sacred Fire's power more since I have no Special Attack investment. Roost to heal off Life Orb, Brave Bird, and any other damage I've taken.

Latios @Soul Dew
Levitate
Timid 6HP / 252SpA / 252Spe
-Calm Mind
-Dragon Pulse
-Grass Knot
-HP Fire

Calm Mind will boost Latios's power to amazing levels. And Soul Dew makes it even more beastly. Dragon Pulse for STAB. Grass Knot for bulky waters and any fat Pokemon that decide to come in. HP Fire gets it's power boosted in the sun, so why not have it? Kills ice and some other potential threats too.

Forretress @Leftovers
Sturdy
Sassy 252HP / 44Atk / 212SpD
-Gyro Ball
-Stealth Rock
-Toxic Spikes
-Rapid Spin

Most of this team is weak to Stealth Rock so I figured Forretress would get rid of them easily. I can also set up my own Stealth Rocks and maybe some Toxic Spikes. Gyro Ball with 0 Speed IVs and a -Speed nature can hurt. I changed the Specially Defensive set to fit my team more properly.

Jumpluff @Leftovers
Chlorophyll
Timid 188Def / 252Spe / 68SpD
-Leech Seed
-Substitute
-Sleep Powder
-Protect

I'm not sure who, but I battled someone with this set on his Jumpluff and it annoyed the crap out of me, so I thought I'd use it. Jumpluff is epic in eternal sun. I don't think anything can outspeed it that isn't Scarfed. Sleep Powder, Substitute, then Leech Seed. Protect if they manage to attack.

Heatran @Choice Scarf
Flash Fire
Rash 6Atk / 252Spe / 252SpA
-Fire Blast
-Earth Power
-Explosion
-HP Grass

With Forretress and Jumpluff and the sun out, it's obvious opponents will try Fire type moves to try and kill them. So, I switch to Heatran to absorb the fire attack. With the sun out, Fire Blast is going to do major damage. Earth Power is for other Fires and Grounds. HP Grass for the waters. And finally, when in doubt, EXPLODE!

I tried to test it on shoddy, but no one was in the ubers catagory so I challenged people in the OU catagory. Everyone quit when they saw ubers...
Constructive critizism is welcome.

Tentacruel instead of fortress in my opinion because it resists a lot of your weaknesses like water and ice. and its a really good sp.def wall!
it can set up toxic spikes as well.
you can change its nature and put sp.atk evs on groudon and add solarbeam for water weakness and ground! but that's all on you!

Forretress actually provides a very useful dragon resistance in the Ubers metagame, so I would advise that you keep Forretress to provide a valuable switch in for all of the Outrages and Draco Meteors flying around.

As powerful as Heatran is in OU, in Ubers it simply is not powerful enough. As weird as it may sound, Palkia is amazing in Sunny Day teams, as it powers up Fire Blast, and, even if your opponent carries Kyogre, you can fry it with Thunder, besides, a 4x resistance to Fire is basically the same as an inmunity
(Thanks to Shnoohgle for the name correction)

Why Fortress? It will get taskn down if sunny day is up and stops you using lava plue.