The development of a "cut off " depression at about 31°s is examined in detail by means of space cross-sections based on routine data, and a time section based on special observations at Woomera. Broad warm and cold frontal zones were found on either side of a barotropic trowal, which, during the occlusion process, broadens and weakens as a result of ascent. Marked wind shifts are found in the cold frontal zone, indicating cold advection, but these are fairly sharp only near the surface. Both wind shift and cooling commence above the low level inversion about 1½ hours before the wind change at the surface, and these changes aloft are accompanied by mamma and a small pressure jump. The thermal ridge and trowal, with appropriate middle cloud mass, during the occlusion process curl around the depression cent re in the manner familiar from satellite photo-graphs. A strong warm front type baroclinic zone in the middle and upper troposphere develops to the northwest of the system during the cutting off process, as a result at least partly of differential vertical motions.
T. Kamiko (Tue,) studied this question.