The tendency to have dry skin is inherited. Dry skin is much worse in the wintertime in the north when the humidity drops to low levels.

dry-skin

Severe dry skin

There is a special form of severe dry skin called ichthyosis. The skin in this disease becomes extremely dry in the winter and forms rectangular dry plates of scale. There are many forms of this problem, but the two most  common are called dominant ichthyosis and sex linked ichthyosis.

Dominant ichthyosis

Sex Linked Ichthyosis