From Bulbapedia, the community-driven Pokémon encyclopedia.
Weather conditions are a feature that was implemented into the Pokémon games in Generation II, and expanded upon in Generations III and IV. During these games, weather depended upon where a battle took place, or even whether a Pokémon had used a specific move or ability. Only one weather condition may be active at a time, and if a move or ability changes the current state of the weather, the previous condition is canceled.
In the second generation, when the first conditions were introduced, some moves came to have an advantage with them, notably, SolarBeam and Thunder, both of which would be nearly deadly with the right conditions.
During the third and fourth generations, many abilities also took advantage of a particular weather condition, some using them to heighten certain stats or to recover HP. Others still would activate the conditions themselves, with two of the three Hoenn-based weather legendaries activating battle-long sun and rain, and the third preventing all weather conditions with its ability.
Current weather conditions
Battling in intense sunlight
- Effect: Increases the power of Fire-type moves by 50%, weakens the power of Water-type moves by 50%, allows immediate firing of SolarBeam, lowers accuracy of Thunder to 50%. Causes Moonlight, Synthesis and Morning Sun to recover 2/3 of max HP. Activates the following abilities: Chlorophyll, Dry Skin, Flower Gift, Leaf Guard, Sun Power. Changes Weather Ball to a Fire-type move and doubles its power, and Castform to its Fire-type form.
- Activating move: Sunny Day
- Activating ability: Drought
- Routes where it is encountered naturally: Eastern Hoenn Water routes (after Groudon is awakened, before it is captured) (Ruby/Emerald); Routes where Terra Cave appears (Emerald)
- Effect: Increases the power of Water-type moves by 50%, weakens the power Fire-type moves by 50%, forces SolarBeam to take 2 turns to gather sunlight, raises accuracy of Thunder to 100%, and allows it to hit through Protect and Detect 25% of the time. Causes Moonlight, Synthesis and Morning Sun to recover 1/4 of max HP. Activates the following abilities: Dry Skin, Hydration, Rain Dish, Swift Swim. Changes Weather Ball to a Water-type move and doubles its power, and Castform to its Water-type form. Also prevents Pokémon from exploding in Pokémon Mystery Dungeon.
- Activating move: Rain Dance
- Activating ability: Drizzle
- Routes where it is encountered naturally: Route 119 (some days) (Ruby/Sapphire/Emerald); Route 120 (always) (Ruby/Sapphire/Emerald); Route 123 (some days) (Ruby/Sapphire/Emerald); eastern Hoenn Water routes (after Kyogre is awakened, before it is captured) (Sapphire/Emerald); Routes where Marine Cave appears (Emerald); Route 213 (sometimes) (Diamond/Pearl); 214 (south leg) (Diamond/Pearl); 215 (always) (Diamond/Pearl)
- Effect: Damages all Pokémon that are not Shadow Pokémon. Changes Weather Ball to a Template:Type2 move and doubles its power, but does not change Castform's form.
- Activating move: Shadow Sky.
- Activating ability: None.
- Routes where it is encountered naturally: Not encountered naturally.
- Effect: Lowers accuracy of all Pokémon battling, doubles the power of Weather Ball.
- Clearing move: Defog
- Activating ability: None so far.
- Routes/areas where it is encountered naturally: Route 210 (north leg) (Diamond/Pearl); Victory Road (path to Route 224) (Diamond/Pearl); Turnback Cave (Diamond/Pearl); Courtyard Colosseum (Battle Revolution)
On the field
There have been several on-field weather conditions, most of which do the same as another on-field weather condition.
There has only so far been only one on-field weather condition where the sun shines brightly. The screen brightens and dims alternately.
There have been two different rain conditions.
- Normal rain: Rain falls. Found in all places where rain is found on the field.
- Thunderstorm: Rain falls heavily, at a lower angle than in the other, and occasionally, lightning will strike and thunder will rumble. Found on Route 119 as part of the four-day rain-thunderstorm-rain-clear cycle. Found on Route 212 on occasion.
There has been only one sandstorm condition. Wind whips sand around, making it difficult to see.
There have been a whopping four snowy conditions.
- Light snow: Snow falls lightly. Found in Snowpoint City.
- Heavy snow: Snow falls more quickly and heavily. Found on Route 216 and in Acuity Lakefront.
- Blizzard: Snow whips around, making it difficult to see. Found on Route 217.
- Diamond dust: Small ice crystals twinkle in the air. Found on certain days in Snowpoint City.
There has been only one fog condition.
- Heavy fog: Thick fog blankets everything. Obstacles and Trainers are difficult to see.
The blindingly-hot sun shines down.
Diamond dust twinkles in Snowpoint.
In the second-generation games, three moves were introduced that could change the weather during a battle to alter the playing field slightly. These moves were Sunny Day, which created five turns worth of intense sunlight and allowed a Pokémon to attack with SolarBeam without waiting a turn; Rain Dance, which gave five turns of heavy rain and increased Thunder's accuracy to 100%; and Sandstorm, which made a wild sandstorm that lasted for the same amount of turns. These three moves could change the course of a battle, with intense sun and heavy rain powering up Fire- and Water-type moves, and powering down the other, respectively, and a sandstorm slightly damaging any Pokémon not of the Rock-, Ground-, or Steel-types.
In the third generation, the title Pokémon of the three Hoenn-based versions had weather-related abilities. Groudon's ability allowed for intense sunlight to fill the arena until the battle ended, or another weather effect took its place. Likewise, its counterpart Kyogre's ability made heavy rain that lasted until the end of the battle or until another weather effect superseded it. Emerald Version's mascot, however, had a different way of affecting the playing field. While Rayquaza is battling, all effects of the weather are essentially negated, though the actual sunlight/rain/sandstorm/hail remains going. Psyduck and Golduck may also have a similar ability.
Another Pokémon, one which was not available in Ruby or Sapphire without trading, also had a weather-based ability. Tyranitar, once fully evolved from a Larvitar captured in FireRed or LeafGreen, has the ability Sand Stream, which causes a sandstorm that lasts until the end of the battle or until another weather-changing move is made. This makes it almost useless for a Tyranitar to have the move Sandstorm itself, as the sandstorm is automatically activated as it comes into battle.
Ruby and Sapphire also debuted another weather-changing move, Hail, which, like Sunny Day, Rain Dance, and Sandstorm before it, changes the weather for five turns, this time to an icy hailstorm. However, this move, and weather effect, have more in common with Sandstorm than with the other two. For the five turns that it's hailing, all Pokémon who are not Ice-type are damaged.
Also in Generation III, one of the 135 Pokémon released was a quirky little Normal-type called Castform. When in a battle where no weather effects were present, Castform is quite unremarkable. However, when any of the effects besides a sandstorm are applied, Castform's type and shape change to match the weather, due to its ability, Forecast. Also, when it is leveled up, it learns a move called Weather Ball, which also changes type with the weather, doubling its power when any weather was in effect. Unlike Forecast, Weather Ball's type differs even in a sandstorm, becoming a Rock-type move.
Within the fourth generation, the weather effects seem to be going strong. At one point in Sinnoh, it is actually possible to travel on a route covered in snow. Also in Generation IV, a new ability was released that serves much like Drought, Drizzle, and Sand Stream, excepting the fact that it permanently activates a hailstorm instead of sunlight, rain, or sandstorm.
Several held items were also introduced that extend the length of a certain weather condition when its activating move was used by the holder by three turns.
Another new weather condition introduced in Generation IV was the fog condition. Instead of having a move to activate it, however, there was a move introduced to clear it.
More interesting things introduced within Generation IV were other conditions that had nothing to do with the weather, but behaved similarly to the weather-activating moves. Like the weather conditions, these moves would affect all Pokémon on the field for five turns, and in various ways. For example, one move would rid Levitating Pokémon of their powers, and force both them and Template:Type2s to take damage from Template:Type2 moves, as well as disabling moves like Fly and Bounce, whereas another, Magnet Rise, makes the user invulnerable to Template:Type2 moves, again for five turns. Also, Trick Room alters the dimensions for five turns, making slower Pokémon attack first; and Tailwind increases the Speed of the user's team for five turns.