A case of an undular bore and prefrontal precipitation in the Australian Alps

Abstract

This study explores the mesoscale processes that led to the development of two prefrontal precipitation events in the Australian Alps on 29-30 October 2010. The synoptic setting was characterized by the passage of an interacting front and prefrontal trough across southern Australia. Observations and model simulations revealed that when the prefrontal trough entered southeast Australia it resembled a density current advancing into a stable nocturnal layer, forming a bore at its leading edge. The bore detached from and propagated ahead of the prefrontal trough and became undular, supported by a wave-ducting mechanism. The undular bore was observed in the Doppler wind field of a radar, parts of..