2 pts. Great answer Jeff. an extra point for adding
worthwhile content.

Can you name two places where tides are diurnal?

What are spring and neap tides and how can you tell by
observing the moon, if a tide will be spring or neap?

Jeff Morris wrote

Halfway between moonrise and moonset is 10 pm local time, which is the
time of
transit of the local meridian. To this we must add the "Local
Establishment" or
the "Lunitidal Interval" (actually the proper terms are "high water full
and
change" or "mean high water lunitidal interval") to get the time of the
next
high tide.

This was published on old charts. My 1867 Boston Harbor chart lists the
"Corrected Establishment" (average of all high water intervals) for Boston
Light
as "XIh XIIm". This mean you add 11 hours and 12 minutes to the time of
local
meridian passage of the moon to get the time of the next high tide.

Tides watches usually require setting the Lunitidal Interval for a
particular
spot. Of course, this only works for semidiurnal tides.