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Negative  Surges  in  the  Southern  Baltic  Sea

5.9.  November  1979
Meteorological  situation
On  2  and  3  November,  Scandinavia  and  the
Baltic  Sea  area  lay  between  an  anticyclone  from
Finland  tracking  southeast  and  a  low  pressure
system  advancing  slowly  from  the  Norwegian
Sea.  The  pressure  gradient  over  the  area  steepened, ­
  and  around  noon  on  3  November  the
whole  Baltic  Sea  region  was  under  the  influence
of  an  intensive  southerly  to  southeasterly  air  flow
that  preceded  the  low  pressure  trough  with  its
associated  frontal  system.  The  trough  deepened
as  it  entered  Scandinavia  and  the  Baltic  Sea  in
the  afternoon  of  3  November.  By  night,  galeforce
  winds  from  southwesterly  directions  had
reached  7-9  Bft.  The  SW  storm  continued  until
the  late  hours  of  4  November,  when  it  veered
west  and  decreased  temporarily  in  the  western
part  of  the  coast  after  the  cold  front  had  tracked
across  the  southern  coast.

Hydrological  response  of  sea  level
Water  levels  had  been  slightly  below  the  mean
values  since  2  November.  On  3  November
around  noon,  the  strong  offshore  wind  caused  a
gradual  fall  of  water  levels.  This  time,  deeper
minima  were  recorded  at  the  eastern  water  level
gauges  than  at  the  western  ones.  The  lowest  values ­
  were  recorded  at  more  or  less  the  same  time
in  the  late  afternoon  of  4  November,  between  18
and  19  UTC.  372  cm  was  measured  at  Wismar,
381  cm  at  Warnemunde,  387  cm  at  Sassnitz,
370  cm  at  Swinoujscie,  and  370  cm  at
Kotobrzeg.

Fig.  5.9.  a  Pressure  pattern  and  wind  field  over  the  Baltic  Sea  on  4  November  1979,12  UTC