• Fire types can be found near gas stations, and during sunny days

• Water types at lakes and other bodies of water as well as while it's raining

• Electric types are found near transforming stations and during thunderstorms

• Ghost type can be found during night, or during the daytime near church/graveyards

• Grass, Bug, and normal types can be found near parks and other green landscapes 

• Normal types can also be found near urban areas.

Pass this along to save a life.

Grimer's can be found by wading in the sewers, and you can get a shiny haunter if you dig up a grave.

was it raining or about to rain?

lol there's a gym right out front of my apartment

I think any Pokemon can be caught anywhere, but location and weather increase the chances of certain Pokemon poping up.