Anchorage Tidal calcs

the easy way is to use a calculator such as bellfield which has "will i go aground feature"/ simple to use and for 11 quid a bargain. (no asooc with the company but may ask for a discount based on the number of times i recommend their product)
 
You could always make yourself a Table:
(You will have to put the [tabs] in yourself)
<ul type="square"> Tidal Difference Time Range Range MHWS MHWN MLWN MLWS
on Dover Port + / - Sp Np
Cowes IoW 0.23 4.1 2.0 4.2 3.5 1.7 0.6
Portsmouth 0.23 4.1 2.0 4.7 3.8 1.8 0.6
Langstone 0.22 4.7 2.0 4.8 3.9 1.8 0.6
Chichester 0.20 4.1 2.0 4.9 4.0 1.8 0.7
Lymington, Np 0.20 4.1 2.0 3.0 2.6 1.3 0.5
Yarmouth Np 0.20 4.1 2.0 3.1 2.5 1.4 0.6
Shoreham 0.05 5.5 3.3 6.2 5.0 1.9 0.7
Dover 0.00 5.9 3.3 6.7 5.3 2.0 0.8
Newhaven 0.00 5.5 3.1 6.6 5.2 1.9 0.5
Brighton -0.01 5.5 3.1 6.5 5.1 1.9 0.6
Southampton -0.01 4.0 1.9 4.5 3.7 1.8 0.5
Folkstone -0.10 5.5 3.3 7.1 5.7 2.0 0.7
Lymington, Sp -0.40 4.1 2.0 3.0 2.6 1.3 0.5
Yarmouth Sp -0.52 4.1 2.0 3.1 2.5 1.4 0.6
Beaulieu River -1.00 3.1 2.0 3.4 2.8 1.5 0.5
Le Harve -1.20 6.7 3.6 7.8 6.5 2.8 1.1
St Vaast -2.20 5.2 2.5 6.5 5.3 2.3 0.9
Swanage 1.7 0.4 2.0 1.5 1.1 0.3
Cherbourg -3.20 5.2 2.5 6.3 5.0 2.5 1.1
Braye, Alderney -4.10 9.8 4.0 6.3 4.7 2.6 0.8
Portland -4.30 4.1 2.0 2.1 1.4 0.7 0.2
Weymouth -4.38 4.1 3.7 2.1 1.4 0.7 0.2
St Peter Port -4.50 9.8 4.0 9.0 6.7 3.5 1.0
Lyme Regis -4.55 4.7 2.2 4.3 3.1 1.7 0.6
St Helier -4.55 9.8 4.0 11.1 8.1 4.1 1.3 [/list]
 
[ QUOTE ]
has anyone worked out how to tabulate on this forum yet?

[/ QUOTE ]

You mean something like -
<font class="small">Code:</font><hr /><pre>
Tidal Difference Time Range Range MHWS MHWN MLWN MLWS
on Dover Port + / - Sp Np
Cowes IoW 0.23 4.1 2.0 4.2 3.5 1.7 0.6
Portsmouth 0.23 4.1 2.0 4.7 3.8 1.8 0.6
Langstone 0.22 4.7 2.0 4.8 3.9 1.8 0.6
Chichester 0.20 4.1 2.0 4.9 4.0 1.8 0.7
Lymington, Np 0.20 4.1 2.0 3.0 2.6 1.3 0.5
Yarmouth Np 0.20 4.1 2.0 3.1 2.5 1.4 0.6
Shoreham 0.05 5.5 3.3 6.2 5.0 1.9 0.7
Dover 0.00 5.9 3.3 6.7 5.3 2.0 0.8
Newhaven 0.00 5.5 3.1 6.6 5.2 1.9 0.5
Brighton -0.01 5.5 3.1 6.5 5.1 1.9 0.6
Southampton -0.01 4.0 1.9 4.5 3.7 1.8 0.5
Folkstone -0.10 5.5 3.3 7.1 5.7 2.0 0.7
Lymington, Sp -0.40 4.1 2.0 3.0 2.6 1.3 0.5
Yarmouth Sp -0.52 4.1 2.0 3.1 2.5 1.4 0.6
Beaulieu River -1.00 3.1 2.0 3.4 2.8 1.5 0.5
Le Harve -1.20 6.7 3.6 7.8 6.5 2.8 1.1
St Vaast -2.20 5.2 2.5 6.5 5.3 2.3 0.9
Swanage 1.7 0.4 2.0 1.5 1.1 0.3
Cherbourg -3.20 5.2 2.5 6.3 5.0 2.5 1.1
Braye, Alderney -4.10 9.8 4.0 6.3 4.7 2.6 0.8
Portland -4.30 4.1 2.0 2.1 1.4 0.7 0.2
Weymouth -4.38 4.1 3.7 2.1 1.4 0.7 0.2
St Peter Port -4.50 9.8 4.0 9.0 6.7 3.5 1.0
Lyme Regis -4.55 4.7 2.2 4.3 3.1 1.7 0.6
St Helier -4.55 9.8 4.0 11.1 8.1 4.1 1.3
</pre><hr />

This is how to do it.
1.Type the text, as you want to be displayed, into a text editor like Notepad which uses a fixed spaced font. (i.e. each character takes up the same space in the line)
2.Copy the text
3. In your post insert the Code instant mark-up
4 Paste in the text you coppied between the opening code tag and the closing tag
e.g. [ code ] Your text here [ / code ]

(I have put in extra spaces so that the markup is displayed)

Jonathan
 
Brilliant! Take one more gold star than Brendan


PS Tidal data for Anchorage is HERE /forums/images/graemlins/wink.gif /forums/images/graemlins/wink.gif
 
You guys are making heavy work out of this!

When you arrive and drop the hook, note the time and depth of water from sounder, (you do need to know if you sounder shows depth under the keel or depth of water).

Look at range of tide at nearest Std port, get the details onto a tidal graph to calculate amount of tide left to either rise or fall. Add or deduct this from your reading from sounder.

Example:

Arrive, sounder shows 6mtrs.
Time 14.00

HW 15.00
Range 3mtrs
Without the benefit of an actual location and therefore tidal graph, lets say .25mtrs of tide left to rise.
So HW at our anchorage will be about 6.25 mtrs of water.
So in this example we can see that with a range of 3mtrs that will leave about 3.25 mtres of water at LW. So if you have a draft of say 1.5 mtrs you will have 1.75 mtrs of water at LW. One other point you have to watch, is the next tidal range going to be greater, are the tides working toward springs from neaps.

I will drive around our approx swing area before dropping the hook, just to make sure we are not going to swing onto shallows when the tide turns.

If I arrive at an anchorage at LW I do similar calculations to see how much chain I nead down.
 
Um, wouldnt the theoretically correct answer be to use an admiralty co-tidal atlas, in NPxxx ?? This would give you the tidal height and rate differences, which may not necessarily correlate with the 'nearest' port, etc...

Of course, the practical answer is to run your tide calc software... /forums/images/graemlins/wink.gif
 
[ QUOTE ]
Um, wouldnt the theoretically correct answer be to use an admiralty co-tidal atlas, in NPxxx ?? This would give you the tidal height and rate differences, which may not necessarily correlate with the 'nearest' port, etc...

[/ QUOTE ]

You got in first. The only problem is that co-tidal charts aren't covered in the RYA syllabus.

Oh, and it's not NP.... (unless you're in the Thames Estuary). Chart 5058 gives co-tidal curves for the whole of the UK and surrounding waters (from Brittany up to Norway) and gives easily understandable instructions for their use.
 
Just answered off the top of my head, havent used co-tidal charts for long time. Might get 5058 for pure interest tho'. /forums/images/graemlins/crazy.gif
 
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