30th July 2005: 06UTC
The image shows a frontal system covering Western Europe. The occluded part of this system, which lies over the Baltic Sea, Denmark and the North Sea is characterised by an elongated surface low. The cold front part is harder to distinguish as it is contained of low clouds. These clouds are found over Switzerland and Southern Germany. Judging the axis of the surface ridge however assume that the surface front lies further to the east.
30th July 2005: 12UTC
Dominated by a high pressure system, convection over the Carpathian Mountains has started. The low over the occluded cloudband has further deepened and is situated between Denmark and Sweden. The confluent flow that can be derived when observing the isohypses over Southwestern Europe and over southeastern Europe may be the cause for the first signs of convection over Switzerland.
30th July 2005: 18UTC
The deepening within the occluded cloudband has continued. Two seperated surface lows are observed. Over the Baltic States a large convective cell is observed. Southward over Lithuania, Poland, Austria a long line of prefrontal convergence is observed all the way up to northern Italy. Along this line a zone of confluent flow, caused by the cyclonic movement over Western Europe and the anticyclonic movement over Eastern Europe, is recognised. The axis of the surface ridge also show the location and orientation of the surface cold front. Embedded to this cold front convection is seen.
31st July 2005: 00UTC
The secondary surface low has shifted northeast towards Estonia. It is still associated with some convectivity which is now found over Russia. Situated within a surface ridge a large MCS is covering Poland. It developed as the convection embedded into the cold front merged with the prefrontal convection.
31st July 2005: 06UTC
The secondary surface low has shifted even further northeast. The convectivity associated before has completely dissolved. The cell over Poland is also partially dissolving. On the leading edge a distinct surface trough is seen.