A reference to relief factors (differences in elevation between the highest point and the lowest point of land in a specified region); such as, hills, mountains, plateaux, valleys, and slopes.

A cloud whose form and extent is determined by the disturbing effects of orography and mountains upon the passing flow of air.

Because these clouds are linked with the form of the terrestrial relief, they generally move very slowly, if at all, although the winds at the same level may be very strong.

A rain shadow desert on the leeward side of a mountain rnge.

Precipitation which results from the lifting of moist air over a topographic barrier; such as, a mountain range: "The orographic precipitation may take place at some distance upwind or a short distance downwind, as well as on the barrier itself."

Rainfall produced by supersaturation of an air mass forced upwards by a mountain range.