39 
On 8 January, light to moderate W - SW and SE winds prevailed over the southern basins of 
the Baltic Sea. As the low approached, the winds veered SW and reached moderate to high 
wind speeds in the western Baltic Sea. A NW - N storm of 6-8 Bft developed in the rear of 
the low and struck the coasts of the Wismar Bight around 15 UTC on 8 January and then, 
around midnight, with even higher severity, the coast of the Pomeranian Bight and parts of 
the central coast. In the early hours of 10 January, the storm, which had veered NE, 
gradually abated as the low retreated southwards. 
Over the southern Baltic, however, the northeasterly gale continued with varying intensity. 
Very strong gusts were recorded, which were due to extremely cold continental air masses 
over the sea (coastal stations reported that on 10 January, at 6 UTC, Kaliningrad recorded 
-22 e C, Klaipeda -25 e C, Liepaja -26 e C, Riga -31 e C and Helsinki -35 e C), the southern parts 
of which were not completely covered by ice. 
On 11 January, the atmospheric pressure in the anticyclone over Scandinavia rose to 1052 
hPa. The steepest gradient, along with a steady NE storm of 8-10 Bft, occurred on the 
southern and southeastern coasts of Sweden. The storm reached its maximum between 06 
and 21 UTC on 12 January, when a wide and flat zone of lower pressure began to form over 
Central Europe, tending to drift northwards. The zone with the steep gradient and strongest 
wind moved towards the Scandinavian coast and the westernmost part of the western Baltic 
Sea, while the southern and southeastern Baltic Sea remained in a field of somewhat weaker 
winds blowing mostly alongshore (Fig. 6.8.2.). It was not until about 00 UTC on 13 January 
that winds on the southern coast began to decrease, although farther offshore and over the 
Baltic Proper the easterly storm continued for several days. 
0° Iff* 2& 30~ ijtf ~ 
Fig. 6.8.2. Pressure pattern and accompanying wind field at 18 UTC on 12 January 1987 
over the southern areas of the Baltic Sea 
Hydrological response of the sea level 
During the surge of 8 - 9 January, 1987, water levels rose first in Wismar and Warnemunde 
(between 12 and 15 UTC on 8 January), when winds in the area veered NW, nearing gale 
force. Between 18 and 21 UTC, in response to the onset of a northwesterly to northerly storm 
of 7-8 Bft in the rear of the cold front, sea levels in the central part of the coast rose rapidly. 
Culmination was first reached in Sassnitz (605 cm at about 03 UTC on 9 January), which 
also recorded the highest mean rate of growth, at an average 10 cm/h (111 cm in 11 hours). 
Culmination was next reached in Swinoujscie, 612 cm at about 07 UTC with an average 
increase of about 9 cm/h, and Kotobrzeg with a two-peaked maximum of 607 and 609 cm