Isentropes show a downward inclined gradient zone (frontal zone), which extends through the whole troposphere.
Temperature advection
The warm advection takes place ahead of the frontal zone, whereas the front
itself is within the region of a strong cold advection. In this cross section the cold advection is
much more pronounced then in the one at 12 UTC and it lies through the whole layer up to
400 hPa.
Relative humidity
Values of relative humidity are high ahead of the frontal zone and low behind it, in
the upper levels. High values can be also observed at the position of convective cloudiness
in north Italy.
Potential Vorticity
PV shows an anomaly that is protruding in the high levels of troposphere at the rear part of frontal zone. This positive PV anomaly can be associated with
cyclogenetic processes in the system of interest.
Omega
Distribution of omega is characterized by negative values (upward motion) within
and above the crowding zone of the isentropes and the highest values can be found between 700 and 500
hPa. Weak positive values (downward motion) can be found behind frontal zone.
Another maxima of negative values can be observed over northern Italy in the
location of convective cell development which also indicates high level of
instability in that region.
Vorticity Advection
Positive values of vorticity advection are located within the crowding zone
of the isentropes from
middle to upper levels.
