As polarizability increases, the dispersion forces also become stronger. Thus, molecules attract one another more strongly and melting and boiling points of covalent substances increase with larger molecular mass. Polarazibility also affects dispersion forces through the molecular shape of the affected molecules.

Does higher polarizability mean higher boiling point?

High polarizability means more covalent character,which means tighter bonding, and therefore means high boiling point.

Why does polarity affect boiling point?

Molecules with higher polarity have greater dispersion forces and therefore stronger dipole-dipole interactions. This greater intermolecular attraction force leads to a higher boiling point. This explains why water (with all its hydrogen bonds) has a high boiling point.