The case described here deals with several interesting phenomena. The main investigation is related to convection within the cold front. The other processes followed here are convergence at the leading edge of the front and convection far ahead over eastern Turkey.
The following theories can describe convection within and in front of the cold front :
Development of the Mesoscale Convective System within the cold front follows closely the course of classical development described here. The MCSs develop during 25th and 26th May at the leading edge of the front which can be followed by satellite loops and numerical model fields of meteorological parameters.
Situation typical for the thickness ridge, ahead of the cold front, is confirmed by the analysis of 300 hPa geopotential field. The moist warm air is advected from the south or south-west which, together with the drier and colder air in the upper levels, leads to potentially unstable stratification of the troposphere. The MCSs develop at the windward side of the orography, ahead of the front, during the night of the 26th May.
The cold front in this case seems to be a Kata cold front. Convection is enhanced by PVA in the left exit region of the jet streak which is more or less perpendicular to the front. Convection is also enhanced through a combination of potential instability (confirmed by the numerical field of Showalter index, VCS, radiosounding and radar data) and frontal and pre-frontal convergence (VCS).
In this case study the Upper level low plays an important role in the convection over eastern Turkey during the 26th May. Convection develops on the edge of an upper level low extending through the upper troposphere (700 hPa and above - not shown here).
The enhancement of convection by PV is followed as the front crosses Turkey from north-west to east. The maximum of PV shows the penetration of stratospheric air into the troposphere, at the rear of the frontal cloudiness.