The answer to 'why is my centipede swarms' is that centipedes are typically solitary pests, but their population can explode under certain conditions. Centipede swarms are often caused by excessive moisture, decaying organic matter, or an abundance of their prey like insects and spiders.
Centipede swarms are a sign of an underlying pest problem in your home. They may indicate high moisture levels, poor sanitation, or an existing insect infestation that the centipedes are feeding on. Addressing the root cause is key to getting rid of centipede swarms long-term.