Surface pressure and temperature in 850 hPa (model fields), Time Sequence: 3h, 29 February to 01 March 2008     

A wave structure covered northern France, West and Southwest Germany. It separated mild air from colder air over England, Central, East and North Europe.

However, we will not investigate this structure any longer. In this chapter we will consider the developments in relation to the rapid cyclogenesis south of Iceland (outside of these maps). In the upper left corner we find relatively mild air approaching UK and a stronger surface pressure gradient.

click upon the link legend T850 hPa or click upon the key symbol (above).

This image reveals the approaching mild air west of Ireland and an increasing surface pressure gradient.

The mild air arrived Ireland and the surface pressure gradient continued increasing.

The warm front arrived West Ireland and West Scotland. The image reveals a strong surface pressure gradient over the northern and central parts of UK. At the upper left corner we find colder air coming from Northwest.

The warm front moved to the east. The cold front/occlusion hit Ireland and West Scotland. The storm field covered Ireand and the northern parts of UK. Gusts up to 56 knots and surface pressure tendencies up to -10 hPa/3h were measured.

The warm front crossed UK and the succeeding cold front arrived Ireland and Scotland. They are connected with intense warm air advection and cold air advection, respectively. Gusts up to 76 knots were registered (North Irish coast).

The frontal system covered UK and parts of the North Sea. The storm field influenced the entire UK, the North Sea and the Belgium, Dutch and German coast.

The storm field moved to the east. The cold air in the cold fronts's rear arrived South Ireland and North England. In Westerland (Sylt, Germany) gusts of 56 knots (Beaufort 11) were registered.

The cold front/occlusion (surface weather chart) moved fast to southeast and extended at 00 UTC from South England to North Germany.

The occlusion arrived at the low mountains of Germany. High surface pressure gradients can be found over UK, Northeast France, Belgium, and the southern and central parts of Germany. Gusts about 40 to 50 knots (flat areas) and up to 86 knots (mountains in Germany) were measured.

The occlusion (surface weather chart) arrived South Germany the surface trough was crossing the low mountains of Germany (cylonic shape of the isobars). Many parts of UK, Benelux Countries, France and Germany were covered by high surface pressure gradients (gusts up to 70 knots in flat areas and 91 knots on mountains).

Occlusion and surface trough moved fast to Southeast. Especially, over Central and South Germany severe gusts (up to 70 knots) were registered. In the Alps even 119 knots were reported.

The occlusion hit the Alps and the cold air rear of the trough covered almost entire Germany. Again severe gusts were measured.

Whereas the cold air continued moving fast from Central to eastern Europe the Alps slowed down this movement. The model exhibits a "ridge" near the Alpine crest that is typical for Foehn-situations.

This image reveals very clearly the typical isobars' shape near the Alps during a Foehn situation and the Alps as the barrier for the cold air (small greenish area extending from the North to the Southwest Alps).

Whereas the gusts decreased over West Germany gusts up to 60 knots (East Germany) and 86 knots (Alps) were observed.

No significant changes happened. We still see very pronounced the Foehn effects near the Alps.