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PLACE SPRING RANGE /metres/
Ijmuiden and Waddeneilander 1.8
Borkum 2.6
Die Ems 3.0
Die Ost-friesischen Inseln 2.7 to 3.2
Die Aussenjade 3.4
Wilhelmshaven 4.2

In the North Sea, strong or prolonged winds and unusual
barometric pressures induce changes in water level and
cause tidal heights to differ from those predicted. For
a general explanation see The Mariner's Handbook.
On the E and S shores of the North Sea, strong onshore
winds raise water levels and strong offshore winds lower
them, the effect being aggravated if the wind is prolonged.
13. The tide is predominantly semi-diurnal off the E coasts
of Scotland and England and progresses from N to S along
the coast. For further details see charts 5058 and 5059
and Admiralty Tide Tables.
Where time references are given in the Tidal Stream
information they are always given in four figure groups,
in which the first two figures are hours and the last
two figures are minutes; the references are to the nearest
five ninutes.
References preceded by a minus /-/ sign are intervals
before high water /HW/; those preceded by a plus /+/ sign
are intervals after high water.
14. Tides and tidal streams. During E gales the tide does
not rise so high, nor falls so low, as at other times.
It rises longest and falls lowest during winds from
between NW and SW.