According to the compendium in game "Largemouth Bass inhabit open and flowing water all around the Southern States. They can be easy to spot, due to swimming energetically near the surface, but less easy to catch. Anglers report that Largemouth Bass didn't seem to care for most lures, but responded well to fresh crayfish. Rainy weather is linked with increased activity. Some say that the San Luis River is home to a Legendary Largemouth Bass"
According to the compendium in game "You are most likely to catch this type of fish when it rains"