Spawn Pool Guide
What actually controls which Pokémon spawn near you, and how to influence it.
What decides a spawn
Wild spawns are influenced by your local biome (urban vs. water-adjacent vs. rural/green space), the current weather boost active on your account, the time of day, nearby PokéStops and Gyms, and whichever seasonal or event-specific spawn pool Niantic has active worldwide or regionally. There's no single official, publicly-published table listing exactly which species spawn where — Niantic doesn't disclose that data, and any list claiming to be a complete live spawn map is really a crowdsourced estimate rather than confirmed fact.
Weather boosts
Six weather conditions each boost two types' worth of spawns and give boosted Pokémon a small CP and stat bump: Sunny/Clear boosts Fire, Grass and Ground; Rain boosts Water, Electric and Bug; Partly Cloudy boosts Normal and Rock; Cloudy boosts Fairy, Fighting and Poison; Windy boosts Dragon, Flying and Psychic; Snow boosts Ice and Steel; Fog boosts Dark and Ghost. Use the Type Effectiveness Chart or Pokédex weather filter to check which weather boosts a given type.
Things that genuinely help
Incense increases spawns directly around you for its duration (and is strongest while walking). Lure Modules attract spawns to a specific PokéStop for everyone nearby. The in-game Nearby/Sightings radar shows which species are currently reachable around your real location — that's the only fully reliable, real-time source for "what can I actually catch right now," since it comes straight from the game rather than a third-party guess.