PokeSurvivor has five weather states: harsh sun, rain, sandstorm, snowfall and fog. Sun boosts Fire and weakens Water; rain boosts Water and Electric and weakens Fire; sand boosts Rock, Ground and Steel; snow boosts Ice; fog boosts Ghost, Fairy and Psychic. Weather can start after minute 2, rolls every 60 seconds at 18%, and lasts 55–75 seconds. The host controls it in co-op.
The five states
Weather is a temporary run event, not a permanent account setting. The five states are:
- Harsh sun: Fire is stronger, Water is weaker.
- Rain: Water is stronger, Electric is slightly stronger, Fire is weaker.
- Sandstorm: Rock, Ground and Steel are stronger; other types take chip damage.
- Snowfall: Ice is stronger; other types take chip damage and move slower.
- Fog: Ghost, Fairy and Psychic are stronger.
The weather is visible as a light tint and particles. The effect applies to both your attacks and enemy attacks, so a rain boost can help the enemy Water attacker as much as your own.
Exact multipliers
| Weather | Boosted | Weakened | Other effect |
|---|---|---|---|
| Harsh sun | Fire ×1.5 | Water ×0.5 | None. |
| Rain | Water ×1.5; Electric ×1.2 | Fire ×0.5 | None. |
| Sandstorm | Rock, Ground, Steel ×1.3 | — | Other types lose 1.2% max HP every 2 seconds; never lethal. |
| Snowfall | Ice ×1.5 | — | Other types lose 1.2% max HP every 2 seconds and move 10% slower. |
| Fog | Ghost, Fairy, Psychic ×1.3 | — | None. |
The boost scales in and out over three seconds when the weather starts or ends. The full value applies in the middle of the state. A hit at the very start or end can be weaker than the table suggests.
When weather starts
The weather check begins after minute 2. Every 60 seconds there is an 18% chance to start a state. A state lasts 55–75 seconds. That works out to roughly one weather event every six minutes on average, but the roll is random; a run can go longer without one.
Weather does not start while you are in a rift arena or during the Arceus event. It also stops when those encounters begin. Do not plan a boss route around a weather state that may expire before the boss.
Biome weighting
Each biome has a weighted pool, not a fixed weather:
| Biome | More likely | Less likely |
|---|---|---|
| Forest | Rain, fog | Sun, snow, sand |
| Cave | Fog, snow | Rain, sand |
| Volcano | Sun, sand | Fog |
The weights change the chance, not the rule. A volcano can still produce fog, and a forest can still produce sun. Use the biome to set expectations, not to predict the next roll.
Chip damage and slow
Sandstorm and snowfall damage every affected Pokémon every two seconds. The player loses 1.2% of max HP per tick if their types are not safe; the damage never reduces the player below 1 HP. Enemies lose 2% max HP + 1 per tick, so the weather can clear ordinary enemies over time.
Snow also applies a 10% movement slow to non-Ice types. That is enough to change a dodge timing but not enough to replace a movement item. The held item guide lists Choice Scarf and other movement options.
Co-op control
The host decides the weather and broadcasts it. Guests see the same state and use the same multipliers. If the host is in a menu or the run is paused, the weather does not advance for the group. The multiplayer guide covers the host rules.
Weather vs type chart vs upgrades
Weather is not the type chart. The type chart decides whether a move is ×1.6, ×0.6 or ×0.3. Weather multiplies the result afterwards. A Fire move in rain can go from ×1.6 against a Grass target to ×0.8 after the ×0.5 weather penalty.
Weather is also not a permanent upgrade. It ends after 55–75 seconds and does not carry between runs. Permanent upgrades are bought per Pokémon and persist on the account. The upgrade guide covers those separately.
The practical rule: check the weather before committing to a type, but do not rebuild the run around it. A strong type matchup in neutral weather is usually better than a weak move that happens to match the current boost.
Quick answers
How long does weather last?
A state lasts 55–75 seconds. The effect fades in and out over three seconds at the start and end.
When can weather start?
After minute 2. The game checks every 60 seconds with an 18% chance. It does not start in a rift arena or during the Arceus event.
Does sandstorm or snow kill the player?
No. The player chip damage is 1.2% max HP every 2 seconds and never reduces the player below 1 HP. It can still leave you vulnerable to another hit.
Who controls weather in co-op?
The host decides and broadcasts the weather. All players see the same state and use the same multipliers.
Sources and scope
These sources were checked on 22 October 2026. This is source-based guidance, not a claim that the site played every route. The live game can change after an update.
- Official weather.js (GitHub main) — Five states, multipliers, timing, chip damage, slow and biome weights.
- PokéSurvivor official types page — Weather summary and type chart context.
- PokéSurvivor official guide — Rain and sun examples.
- Official news — Weather introduced on 8 October 2026.