29 JULY 1997 - DIAGNOSIS FOR 06.00 UTC WITH HELP OF VERTICAL CROSS SECTIONS

by ZAMG


29 July 1997/06.00 UTC - Meteosat IR image; red: weather observation stations; position of vertical cross section indicated
Vertical cross sections are an additional, different look into the physical-meteorological state of the troposphere which sometimes enhances or even detects special situations. The image above shows the course of the chosen vertical cross section from France across both cloud systems discussed before, i.e. across the area of Jet Intensification (compare Conceptual Models: Front Intensification by Jet Crossing ) in the western, and the area of convergence and Cb activity in the eastern cloud system. The red crosses represent weather stations within a pre-selected distance from the cross section line which are projected vertically on this line for a better representation of the situation at the surface. The grid in cyan and black is related to grid-points of the numerical model of ECMWF used for these purposes.
29 July 1997/06.00 UTC - Vertical cross section; black: isentropes (ThetaE), red thin: temperature advection - CA, red thick: temperature advection - WA, orange thin: IR pixel values, orange thick: WV pixel values
29 July 1997/06.00 UTC - Vertical cross section; black: isentropes (ThetaE), magenta thin: divergence, magenta thick: convergence, orange thin: IR pixel values, orange thick: WV pixel values
29 July 1997/06.00 UTC - Vertical cross section; black: isentropes (ThetaE), green thick: vorticity advection - PVA, green thin: vorticity advection - NVA, orange thin: IR pixel values, orange thick: WV pixel values
29 July 1997/06.00 UTC - Vertical cross section; cyan thick: vertical motion (omega) - upward motion, cyan thin: vertical motion (omega) - downward motion, magenta thin: divergence, magenta thick: convergence, orange thin: IR pixel values, orange thick: WV pixel values pixel values
The images above show the vertical distribution of relevant parameters for both cloud systems which show up as broad maxima of the orange lines: the western one around gridpoint 32/24, the eastern one around gridpoint 35/25. The most important facts are summarised as follows:

SUB-MENU OF 29 JULY 1997
DIAGNOSIS OF THE EASTERN CLOUD FEATURE - CONCEPTUAL MODELS "CONVERGENCE CLOUDINESS" AND "CUMULONIMBUS (CB) AND MESOSCALE CONVECTIVE SYSTEM (MCS)"
VERY SHORT RANGE FORECAST (VSRF) TILL 18.00 UTC