The Intensification of the front is represented by the
PVA
thickness
PVA
which indicates cloud enhancement due to the
curvature
shear
of jet crossing. This signal can also be detected in
IR images
WV images
WV images
as dark stripes or dark areas due to
sinking
rising
sinking
motions. The presence and location of the Jet are represented by the Isotachs, which indicate the lines of equal
vorticity
speed
speed
. The maximum observed speed indicates the location and orientation of a Jet Streak. When a Jet Streak crosses a frontal
zone with a
small
large
large
acute angle an increase of cloudiness in the
left
right
left
exit region of this crossing jet streak can be observed.