Vertical Cross Section: 30 July 2005:18UTC

Isentropes
To the west the cold frontal character with foreward aligned isentropes is still well observed. Till 700 hPa the troposphere is clearly governed by an unstable stratification. In the satellite image the prefrontal convergence line is well observed. In this case the isentropes also show an unstable region in the lower troposphere.

The VCS was laid from position A to B. Click the image to enlarge.

Temperature Advection
Whereas the cold front is characterised by cold air advection stretching up to 300 hPa the prefrontal convergence line is dominated by WA. This might contribute to rising motions and a further enhancement of the unstable situation.

Convergence
Especially in the lower layers of the troposphere maxima of convergence are observed. Within the prefrontal convergence line, around 50N20E a pronounced maximum near 800 hPa is observed. This will further contribute to an enhancement of the unstable conditions and to the devlopment of thunderstorms.

Vertical Motion (Omega)
The values for the rising motions correlate with those of the convergence. Within the cold front and the prefrontal convergence line maxima for omega are found.