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6.17  January  2000
Meteorological  situation
On  15  -  17  January  2000,  the  three  days  preceding  the  storm  surge,  northwesterly  air  flow
prevailed  over  the  North  and  Baltic  Seas.  This  flow  was  generated  by  a  wide,  quasistationary ­
  high-pressure  system  over  the  northeastern  North  Atlantic.  Atmospheric  pressure
in  the  centre  of  this  high,  which  was  located  off  Ireland,  exceeded  1045  hPa.  Along  the
eastern  edge  of  the  anticyclone,  successive  low-pressure  troughs  from  the  Arctic  waters
northeast  of  Scandinavia  tracked  S  -  SE  across  the  Baltic  Sea  towards  the  Russian  plains.
On  17  January,  a  zone  of  steepening  pressure  gradient  formed  over  the  western  basins  of
the  Baltic  Sea  and  soon  spread  eastwards.  The  wind  veered  N  -  NE  and  increased  to  gale
force  7  -  8  Bft  and  locally  9  Bft.  This  development  continued  on  18  January  until,  in  the  early
hours  of  19  January  (Fig.  6.17.1.)  the  wind  abated  slightly,  but  not  below  4  -  6  Bft.
On  20  January,  as  successive  low  pressure  troughs  travelled  southeast  across  Scandinavia
and  the  Baltic  Sea  towards  Bielorussia,  the  wind  backed  NW  -  W  and  increased  again  to  6  -
7  Bft  towards  evening,
The  cold  front  connected  with  this  trough  first  crossed  the  central  and  eastern  parts  of  the
coast,  i.e.  Kotobrzeg  and  Swinoujscie,  shortly  before  midnight  in  the  night  of  21  January  and,
some  hours  later,  between  03  and  05  UTC  on  21  January  -  the  regions  of  Warnemunde  and
Wismar.  After  the  passage  of  the  cold  front  the  wind  veered  N  -  NE,  increased  to  7-9  Bft  and
became  gusty  again  due  to  below-zero  temperatures  of  the  intruding  Arctic  air  (Fig.  6.17.2.).
The  storm  lasted  until  the  afternoon  of  21  January,  when  the  gradient  weakened  and  the
wind  decreased  to  5-6  Bft  locally,  first  beginning  in  the  western  part  of  the  coast.
Soon  after  midnight  the  wind  backed  W  -  SW  and  decreased  gradually.

Fig.  6.17.1.  Pressure  pattern  over  Europe  and  wind  field  over  the  southern  Baltic  Sea  at  00
UTC  on  19  January  2000  -  an  example  of  the  long-lasting  northerly  air  flow  over  Europe
which  often  causes  wind  set-up  along  the  southern  coast  of  the  Baltic  Sea