Dry skin can be hereditary but often comes with weather changes, over washing or simply age! 

Your skin cells do not produce enough oil, like a brick wall with out glue, the cells start flaking and the skin feels rough. You also lack sebum (the oils that coat the surface). Without this waterproof layer, the skin's water evaporates hence the tight feelings.

The French secret is to maintain water in the skin by preventing its evaporation!