The Mesoscale and Microscale Structure and Organization of Clouds and Precipitation in Midlatitude Cyclones. XIII: Structure of a Warm Front

Mesoscale measurement from radars, aircraft and rawinsondes, and synoptic and satellite data are used to provide a detailed description of a warm front as it approached the Washington Coast. In many respects, the warm front was consistent with the classical model: temperature rises were concentrated within a forward-sloping frontal zone, winds veered with height and lapse rates were more stable within the frontal zone, clouds and precipitation were produced by upglide over the warm-frontal surface and, as the warm front approached, clouds lowered and precipitation generally increased. However, in several important respects the warm front differed from the classical picture. Air flowed through the warm front and the warm-frontal zone. Also, the warm-frontal zone had a “staircase” profile, with some segments nearly horizontal and other segments with steep slopes. Finally, precipitation was by no means uniformly distributed; instead, it occurred in both irregular and banded-shaped mesoscale features.