30 
storm gradually decreased to 10-8 Bft. On 20 and 21 January, NW to W winds of 7-8 Bft, with 
a decreasing tendency, were observed . 
Fig. 6.4.1. Route of the low-pressure centre between 17 January, 18 UTC, and 19 January, 
12 UTC; pressure pattern and wind field on 18 January 1983, 18 UTC 
A more detailed study of the wind field along the southern coasts allows an analysis of the 
relationship between the impact of the wind and resultant sea level variations on the shores. 
On 18 January, the initially SW to W-SW alongshore winds of 7-8 Bft grew in force, reaching 
10 Bft in gusts, and backed to offshore directions which were S-SW at times, especially in 
the westernmost parts of the basin. From about 9 UTC, however, winds on the southern 
Baltic coasts veered sharply, developing into a NW storm of 10-11 Bft in the Bornholm area 
as early as noon. Flowever, winds then began to veer W - NW (8-9 Bft) on the southern 
coasts, first in their central parts and later in the west. At about 18 UTC on 18 January, and 
about 00-03 UTC on 19 January, winds veered NW - N at 7-9 Bft, decreasing very slowly. 
Hydrological response of the sea level 
On the day preceding the storm, sea levels in the western part of the coast were 
insignificantly higher than the normal values (e.g. 500-510 cm in Wismar), and were 
moderately high in the central coastal area (e.g. 550 cm in Sassnitz and Swinoujscie). The 
severe storm on 18 and 19 January, and especially the wind field pattern along the coast, 
initially (18 January) caused a further differentiation of water levels in the two coastal areas. 
Then, on 19 January, water levels on the entire coast rose rapidly and exceeded the alarm 
levels. 
In the western part of the coast, the stormy offshore winds caused sea levels to fall by about 
10 cm/h. Levels remained very low for about 8 hours, e.g. 410-415 cm at Wismar. On 19 
January at midnight, when the wind veered suddenly WNW to NW, sea levels began to rise 
rapidly at a rate of 28-29 cm/h and reached their maximum on 19 January between 13 and 
14 UTC. The maximum values in Wismar and in Warnemünde were 634 cm and 617 cm, 
respectively. The difference between the extreme values, which developed in the course of 
18 hours, exceeded 220 cm in Wismar, and about 190 cm in Warnemünde. 
Farther east, at about 9 UTC on 18 January, the immediate reaction of water levels to the 
wind impact is clearly seen in Kotobrzeg and, slightly less pronounced, in Swinoujscie. Wind 
directions veer slightly and begin to oscillate between WSW and W, i.e. they sometimes blow