barrier theory of cyclones
barrier theory of cyclones[′bar·ē·ər ‚thē·ə·rē əv ′sī‚klōnz]
A theory of cyclone development, proposed by F.M. Exner, which states that a slow-moving mass of cold air in the path of rapidly eastward-moving warmer air will bring about the formation of low pressure on the lee side of the cold air; analogous to the formation of a dynamic trough on the lee side of an orographic barrier. Also known as drop theory.