Most severe negative surges on the southern Baltic Sea coast 
59 
December 2001 
Wismar —•—Warnemünde Sassnitz » Swinoujscie — —Kotobrzeg MSL 
Fig. 5.18. b Variations of sea level decrease during the storm surge of 20 to 21 December, 2001 
5.19. January 2005 
Meteorological situation 
Late on 7 January, an active low pressure centre 
formed west of Ireland in the westerly air flow 
over Europe. In the course of 8 January, the low 
crossed the Norwegian Sea, southern Norway 
and central Sweden, deepening, and reached the 
Aland Islands at 00 UTC on 9 January, with 
961 hPa measured in its centre. At 03 UTC, the 
centre entered southern Finland and, slowing 
down, meandered toward the area north of Lake 
Ladoga, where it arrived around 12 UTC. From 
there, the low veered southeast, filling soon. 
The frontal system associated with the low ini 
tially did not influence the wind direction as it 
crossed the Baltic Sea region, but behind the 
warm front tracking across the Baltic Sea in the 
morning of 7 January, the strong westerly wind 
soon backed. On 8 January, as the fast moving 
centre deepened quickly and the pressure gradi 
ent was steepening, the southwesterly storm 
gradually increased in severity, reaching 10 Bft 
between 21 UTC on 8 January and 03 UTC on 
9 January as the occluded front advanced east. 
The strong wind later veered west and gradually 
weakened towards evening (Fig. 5.19. a). 
Hydrological response of sea level 
In spite of the strong winds, sea levels remained 
close to the mean values until around noon on 
8 January. They began to fall around 18 UTC, 
after the strong wind had veered to southwest 
erly directions. In response to the heaviest phase 
of the west-southwesterly storm behind the 
occluded front, levels remained below 380 cm 
from 00 UTC to 10 UTC on 9 January in the 
western part of the coast. 
The recorded minima were: 352 cm in Wismar at 
07 UTC, 379 cm in Warnemünde and 403 cm in 
Sassnitz, both at about 04 UTC, and 410 cm in 
Swinoujscie at 05 UTC. The variations of sea 
level values between 12 UTC on 8 January and 
12 UTC on 9 January in Kotobrzeg could not be 
recorded due to a malfunction of the gauge.