MSG IR10.8 imagery with Surface pressure and lightning: time sequence

18th August 2004: 12UTC
This image shows the surface pressure in combination with the lightning detection (last 15 minutes). At this stage in the development we cannot see a mesoscale structure from the surface pressure pattern.

18th August 2004: 15UTC
At 15 UTC we find a mesoscale low (near or in front of the line-structures lightning) and at the rear a mesoscale high. (Further to the west we see a generally decreasing pressure due to a approaching cyclone)

18th August 2004: 18UTC
The squall line is at its maximum intensity. In the southern part of the lightning detection (about 48°N / 5°E) we see very clearly the mesoscale surface low and just west of the lightning activity a mesoscale high (1003.9 and 1007.1 hPa, respectively).

18th August 2004: 21UTC
Ahead of the squall line we find relatively low surface pressure and high surface pressure at the rear.

19th August 2004: 00UTC
The pattern of mesoscale lows and highs can no longer be recognised.