Weather and terrain
Sun, rain, sandstorm, snow and the four terrains: what they change, how long they last and how they start.
Weather and terrain are field effects that change a whole battle for several turns. Weather affects every Pokémon on the field, while terrain only affects Pokémon that are standing on the ground. Only one weather and one terrain can be active at a time, and a new one replaces the old.
The weather
- Harsh sunlight: Fire moves are 50% stronger, Water moves 50% weaker, and nobody can be frozen. - Rain: Water moves are 50% stronger and Fire moves 50% weaker. - Sandstorm: at the end of each turn every Pokémon that is not Rock, Ground or Steel loses 1/16 of its maximum HP. Rock types also get a 50% Special Defense boost. - Snow (Generation IX): raises the Defense of Ice types by 50%. It replaced Hail, which instead dealt 1/16 damage to every non-Ice Pokémon each turn.
Some Abilities (and the Safety Goggles item) make a Pokémon immune to sandstorm damage.
Extreme weather
Three special Abilities create weather that cannot be removed by ordinary moves. Desolate Land (Primal Groudon) gives extremely harsh sunlight where Water moves fail, Primordial Sea (Primal Kyogre) gives heavy rain where Fire moves fail, and Delta Stream (Mega Rayquaza) creates strong winds that remove the weaknesses of Flying types. They end when the Pokémon that made them leaves the field.
How long it lasts and how it starts
Weather from a move, or from an Ability in Generation VI and later, lasts 5 turns. If the user holds the matching rock, it lasts 8 turns: Heat Rock for sun, Damp Rock for rain, Smooth Rock for sandstorm and Icy Rock for snow or hail.
Moves such as Sunny Day, Rain Dance, Sandstorm and Snowscape start weather, and so do Abilities: Drought (sun), Drizzle (rain), Sand Stream (sandstorm) and Snow Warning (snow). Koraidon's Orichalcum Pulse also summons sun.
The four terrains
Terrain was introduced in Generation VI and lasts 5 turns (8 with a Terrain Extender). It only affects grounded Pokémon, so Flying types and Pokémon with Levitate are skipped.
- Electric Terrain: Electric moves are 30% stronger (50% before Generation VIII) and grounded Pokémon cannot fall asleep. - Grassy Terrain: Grass moves are 30% stronger, and grounded Pokémon recover 1/16 of their maximum HP each turn. Earthquake, Bulldoze and Magnitude are halved. - Misty Terrain: Dragon moves do half damage to grounded Pokémon, and they cannot get status conditions or confusion. - Psychic Terrain: Psychic moves are 30% stronger, and grounded Pokémon cannot be hit by priority moves.
Abilities that make terrain include Electric Surge, Grassy Surge, Misty Surge and Psychic Surge, and Miraidon's Hadron Engine sets up Electric Terrain.
Why it matters in a team
Weather teams pair a setter with Pokémon that benefit, such as a Drought user with Chlorophyll sweepers, or a Sand Stream Pokémon with Rock types. Terrain does the same on a smaller scale. The Utility Umbrella item makes its holder ignore rain and sun, which can protect against an opposing team's plan.