GL: Tidal Currents

[Gregory Han]

Well tidal currents can be frustrating

Yes the tide current (TC) will get much stronger through GA and SC as
the tide range can go from 3' which is normal along the east coast to
more than twice that..  Think of the tide as a wave hitting the coast
and flooding and ebbing through a series of very complicated channels
and man made cuts. Through GA you will be going up one river through a
cut and back down another river.  You will get opposing currents on
one leg and following currents on the other leg all in one afternoon.
If the tide wave comes up one river faster than the other t will
create a water level difference that drives a strong current through
cut between them.

In NC the narrow boundary islands and frequent cuts to the ocean will
create an following current approaching the cut on an ebbing tide
which immediately switches to an opposing current as you pass the cut.
Going up Winah Bay toward Wilmington, you can have an opposing current
in one instance which switches to a Very Strong following current
going through Snows Cut as you follow the stream that shoots out
Carolina Cut, then an opposing current all the way to Wrightsville
Beach.

On top of that wind acting on the local channels and bays and blowing
along shore on the open coast can cause major changes in the amplitude
 of the HW and LW levels.

Most people believe that the tide level and the TC should be in phase,
i.e the tide slack is at HW and LW.  This is modified when you have a
long channel with the Hudson as an extrime example. In that case the
HW is max flood and LW is max ebb.  Most places are some where in
between the two extremes.  So just looking at the tide elevation is
not enough to know the TC.

This is too complicated to try to figure out so that you should
instead consult a tide and TC program or look at the NOAA TC tables.
Nobeltec for example has a great tide program that displays the TC
vectors right on the charts.

On Mon, May 26, 2008 at 9:09 AM, M S <valhalla360 at yahoo.com> wrote:
> I grew up on the great lakes and while I understand the basic principals of tides, I can't seem to get the currents right.
>
>  I check the tides along the route we will be following and think the current should be going with me, but more often than not, it's the exact opposite.
>
>  Anyone have some guidance? We are heading north out of florida and my understanding is the tides and associated currents get stronger as we go north.
>
>  Thanks
>
>  Mike & Tammy
>  Valhalla II
>  Gemini 3400
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-- 
Greg and Susan Han
Allegria -- Krogen Whaleback #16