Precipitable water (top;
cm, every .2 cm, starting at 5.8 cm) and 900 hPa relative vorticity
(bottom; x 10-4 s-1, every 15 x 10-4 s-1
starting at 0 x 10-4 s-1) for the AHW 2.2 run of
Hurricane Katrina (2005) at 0140, 0150,
0200 and 0210 UTC 29 September.
The mesovortex in the western eyewall of Katrina can be tracked
cyclonically around the center to due south, due east and
north-northeast of the center during this 30 min time span. Each
precipitable water maximum is co-located with a maximum in relative
vorticity that achieves its highest value while rotating through
the downshear (northwest) eyewall.