No - LAT is "Lowest Astronomical Tide" or the lowest tide that would be predicted. LLWLT,
or "Lower Low Water Large Tide" is the average of the lowest low water for each year in a
19 year cycle.

Presumably, LAT would be the lowest of the lowest low water in the 19 year cycle, not the
average.



"The_navigator©" wrote in message
...
Here (and the UK I believe) it is the "lowest astromical tide". If you
think about it, that is the only sensible datum for a _sounding_!

Cheers MC

Jeff Morris wrote:

If you were going to take the time to look it up, you could have at least said how it
is
defined.


"Donal" wrote in message
...

"Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message
...

How old is that chart? All of my US charts from the recent past use MLLW

as the datum for

soundings. I even checked in my Chesapeake ChartKit to see if they were

different.

OK - Here's a quiz: What's the meaning of LLWLT?

Lower Low Water Large Tide.


Sounds similiar to LAT.


Regards


Donal
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