29th May 2005: 00UTC
The occlusion of the frontal band is easily picked up by the surface low over the Shetland Islands. Central Europe is still experiencing fair summer weather with a large high pressure system superimposed. Between Albania and Greece confluent flow is experienced.
29th May 2005: 06UTC
Unlike the geopotential height of the upper layers of the troposphere only a very weak pressure gradient at the surface can be recognised within the frontal band.
29th May 2005: 12UTC
29th May 2005: 18UTC
The 140 gpm isohypsen shows a trough just in front of the N-S oriented frontal system and a ridge further away over Austria. This region should be looked at using other (derived) parameters, but it is an indication of an intensifying north-south wave amplitude and development of thunderstorms.
30th May 2005: 00UTC
The trough just at the leading edge of the front is still seen. It is superimposed by two large MCSs.
30th May 2005: 06UTC
The trough at the leading edge of the front is still seen, but appears weaker.
30th May 2005: 12UTC
The 120 gpm isohypsen shows a trough just in front of the N-S oriented frontal system and another trough further to the east, over Turkey. The troughs mark the position where convection is found. This regions should be looked at using other (derived) parameters, but the surface height does give an indication where potential development is observed.
30th May 2005: 18UTC
At the leading edge of the front several MCSs are seen. The trough has even further deepened as the 100 gpm isohypse is now superimposed (compare with 6 hours prior). The 120 gpm shows a trough over Croatia where still some CBs are seen.
31st May 2005: 00UTC
At the leading edge of the front a pronounced surface trough is seen. It marks the location where previous several convective cells were seen emerging.