The answer to 'why is my termite swarms' is that termite swarms typically occur when a termite colony has reached maturity and is ready to reproduce. Termite swarms are a natural part of the termite life cycle and are a sign that you may have an active termite infestation in your home.
Termite swarms typically occur in the spring or early summer when the weather warms up. The winged termites, known as alates, emerge from the colony to mate and establish new colonies. Seeing termite swarms inside your home is a clear indication that you have an active infestation and should take action to address it.