The Mesoscale and Microscale Structure and Organization of Clouds and Precipitation in Midlatitude Cyclones: XVI: Three Dimensional Airflow and Vertical Vorticity Budget for a Warm Front

Abstract

The three-dimensional structure of a warm front and its precipitation features are caused using due-Doppler radar data and supporting mesoscale measurements. Evidence is presented to support a staircase-like structure of the warm-frontal surface and significant flow of air through front from the warm side. The cyclonic vertical vorticities within both the principal banded and nonbanded precipitation features were very weak. The primary source of the vertical vorticity appears to have been advected horzontally from behind the frontal zone by a strong low-level inflow. Vortex streteching was generally weak. Tilting terms is in the vorticity budget were primarily sinks. Kinematic factors that must have played a role in the formation of the banded and irregular precipitation feature associated with this front are discussed and some generalizations are made to other preciptations systems.