Temperature Advection:
The zeroline of Temperature Advection can be found in the center of the Upper Level Low, characterised by a minimum in the
cloud signals. WA and CA maxima are close to the boundaries. This is very typical and indicates a movement of the Upper
Level Low. In this special case the strong WA is connected to the cloud band at the eastern border.
PVA:
There is a distinct PVA maximum at high levels within the eastern border of the Upper Level Low. Such a PVA maximum is not
in every case recognisable but only in cases where a movement of the system exists; it represents the displacement of the
vorticity maximum. In this case such a movment can be observed. This has also be stated in the field of TA.
Relative Vorticity:
There is a large and deep vorticity maximum. This is very typical and indicates a well defined low pressure system.
Potential Vorticity:
The isolines show that stratospheric air has protruded downward to about 500 hPa. This is in conformity with the ideal
configurations of an Upper Level Low.