Sunny:
>Increases the power of Fire-type moves by 50%.
Decreases the power of Water-type moves by 50%.
Allows SolarBeam to be used instantly.
Lowers accuracy of Thunder and Hurricane to 50%.
Causes Moonlight, Synthesis, and Morning Sun to recover ⅔ of max HP (full HP in Generation II).
In Generation V, causes Growth to raise Attack and Special Attack two stages each.
Activates the following Abilities: Chlorophyll, Dry Skin, Flower Gift, Forecast, Leaf Guard, Solar Power.
Removes the chance of Harvest failing to restore a consumed Berry.
Changes Weather Ball to a Fire-type move and doubles its power, Castform to its Sunny form, and Cherrim to its Sunshine form.
Reduces the chance of Pokémon becoming frozen.
Rain:
>Increases the power of Water-type moves by 50%.
Decreases the power of Fire-type moves by 50%.
Causes SolarBeam to only deal half of its normal damage.
Allows Thunder and Hurricane to bypass accuracy check.
In Pokémon Diamond and Pearl, allows Thunder to hit through Protect and Detect 30% of the time.
Causes Moonlight, Synthesis, and Morning Sun to recover ¼ of max HP.
Activates the following Abilities: Dry Skin, Forecast, Hydration, Rain Dish, Swift Swim.
Changes Weather Ball to a Water-type move and doubles its power, and Castform to its Rainy form.
Can be lengthened from 5 to 8 turns with the use of the Damp Rock.
Prevents Pokémon from exploding in Pokémon Mystery Dungeon.
Sand:
>Damages all Pokémon who are not Rock-, Ground-, or Steel-type.
Does not damage Pokémon with the following Abilities: Sand Veil, Sand Rush, Sand Force, Overcoat, Magic Guard
Raises the Special Defense of all Rock-type Pokémon by 50% (Generation IV onwards).
Causes SolarBeam to deal only half of its normal damage.
Causes Moonlight, Synthesis, and Morning Sun to recover ¼ of max HP.
Activates the following Abilities: Sand Veil, Sand Force and Sand Rush.
Changes Weather Ball to a Rock-type move and doubles its power, but Castform stays in its normal form.
Hail:
>Damages all Pokémon who are not Ice-type.
Does not damage Pokémon with the following Abilities: Ice Body, Snow Cloak, Magic Guard, Overcoat.
Allows Blizzard to bypass accuracy check in Generation V.
In Pokémon Diamond and Pearl, allows it to hit through Protect and Detect 25% of the time.
Causes SolarBeam to deal only half of its normal damage.
Causes Moonlight, Synthesis, and Morning Sun to recover ¼ of max HP.
Activates the Abilities: Forecast, Ice Body, Snow Cloak.
Changes Weather Ball to an Ice-type move and doubles its power, and Castform to its Hail form.
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