This region receives less than 250 mm (10 in) of rain a year and includes most of Baja California, western Sonora, and the northern section of the Central Plateau.
These areas can experience frost and freezing during the winter.
Low nighttime temperatures in winter are typically around 5°C
Highest temperatures usually reach about 35°C, but they may get to 40° C.
Includes parts of Nuevo León and Tamaulipas, most of the Western Sierra Madre and many mountainous and volcanic areas in western, central and southern Mexico.
Altitude affects rainfall amounts and seasonality.