A diagnostic study of a monsoon depression that developed over north-western Australia in February 1994 is presented. The analyses are based on gridded data from the Australian Bureau of Meteorology’s Tropical Analysis System. After remaining quasi-stationary for several days after its formation in the monsoon trough, the depression drifted slowly southwestwards along the coast of Western Australia and eventually weakened. The evolution is exemplified by time-height cross-sections of various kinematics quantities as well as the apparent sources of heat, moisture and potential vorticity. A prominent feature of these diagnostic fields is the impact of convective and diabatic processes on the development. The structure of the depression was very similar to the few monsoon depressions that have been documented over the Indian subcontinent. The formation of the depression coincided with the passage of an upper-level mid-latitude trough and a low-level anti-cyclone to the south, but the extent to which the genesis was influenced by these disturbances is unclear.
Hell et al. (Sun,) studied this question.