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2013а]. In the early hours of 28 th October, the storm 
crossed the south of the United Kingdom and moved 
across the southern North Sea towards Denmark. 
About noon, the first hurricane force gusts (12 Beaufort 
(Bft), > 32.7 m/s, > 118 km/h) were measured on the 
German North Sea coast. The weather station at Sankt 
Peter Ording recorded a gust of 47.7 m/s at 12:30 UTC, 
the maximum value in the meteorological network of 
Deutscher Wetterdienst (German National Meteoro 
logical Service). At that time, the centre of the storm 
was located off the northwest coast of Denmark with 
a core pressure of about 968 hPa. Remarkable about 
this storm event were the high sustained winds. Not 
only the gusts but also the 10-minute sustained wind 
speeds reached hurricane force, especially in northern 
Schleswig-Holstein. At the station Strucklahnungshorn, 
e.g., a 10-minute sustained wind of 38 m/s was record 
ed. During the storm's further shift towards southern 
Scandinavia, the Danish weather station of Kegnaes 
Fyr, a lighthouse on the Baltic Sea coast near the bor 
der of Schleswig-Holstein/Germany, recorded a gust of 
53.5 m/s (Fig. 1). 
About one month later, on 4 th December 2013, low 
Xaver formed from a warm front wave across the North 
Atlantic south of Greenland. It rapidly strengthened to 
a severe storm [DWD 2013b]. On its way to Southern 
Sweden, a squall line in connection with the cold front 
of the storm reached northwestern Germany in the af 
ternoon of 5 th December, along which the first hurricane 
force gusts occurred in the German area. Storm Xaver 
hit its peak development on 5 th December at 18 UTC 
with a central pressure of 960 hPa over southern Swe 
den. At that time, the cold front lay across the Western 
Baltic Sea and caused hurricane force gusts also in that 
region. Across the North Sea, the wind turned to north 
western directions which led to several severe storm 
surges. While on 6 th December Xaver relocated only 
slowly towards the Baltic states, the German North 
Sea and the Baltic Sea regions still experienced stormy 
weather with peak gusts of hurricane force. In the 
course of the day, the wind turned from west to north 
west also on the Baltic Sea. The highest gusts on 5 th 
and 6 th December were between 40 m/s and 45 m/s. 
Notable are the sustained high wind speeds, persisting 
during the 6 th December and weakening only during 
the course of 7 th December in the Baltic Sea. The wind 
speed showed noticeable variations of intensity due to 
high atmospheric instability. 
Overall, storm Xaver caused mostly lower wind speeds 
in the German North Sea area and in Schleswig-Holstein 
than storm Christian, while it was the opposite in the 
German Baltic Sea region. 
Results of the Measurements at the FINO Platforms 
FINOl 
Storm Christian approached FINOl from the south 
west. Already during the early morning of 28 th October 
2013 (4 UTC) atmospheric pressure decreased below 
990 hPa at the height of the platform deck (22.5 m, in 
the following all heights refer to marine chart zero/ 
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