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World of Ham Radio 1997
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1997-02-01
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NOTES ADDED BY KEN TRACY. SEE ALSO TIDES.DOC
The subordinate station data I have added for the Chesapeake Bay
was taken from the 1993 NOAA pubs "Tide Tables" and "Tidal Current
Tables", Atlantic Coast of North America. Both these pubs are
available at the NAS Patuxent River Station Library, among other
places. They seem to get the new year pubs in early December.
Adding these stations is mind-numbing work. I did my best to get
it right, but beware. Verify it with your own observations. I ran
a few comparison checks and found nothing obviously wrong. I
checked some tides against predictions in the papers, and from the
books. The few differences I noted were about 1 minute or .1 feet.
Plenty good enough for our purposes. If you play it closer than
that, you need wheels on your keel! I think I've covered the whole
Bay well, but you may want to add a few that are farther up some of
the rivers. When you print out a station the LAT/LON prints out
too. That will give you a pretty good idea where it is, but don't
even think about using those coordinates for navigation--like
LORAN!
Notice there are two types of files: TID and CUR. To use either
you must first load a station with the appropriate suffix--TID for
tides, and CUR for currents. You can set the default for any one.
I have chosen Drum Point tides. When you start up, the program
will want to print out data to the screen for your default station.
Just keep entering Q to get to the menu without that.
Many people think that slack water occurs at high and low tide.
Here's a quote from the Tidal Current Tables: "It is important to
notice that the predicted slacks and strengths given in this table
refer to the horizontal motion of the water and not to the vertical
rise and fall of the tide. The relation of current to tide is not
constant, but varies from place to place, and the time of slack
water does not generally coincide with the time of high or low
water, nor does the time of maximum speed of the current usually
coincide with the time of most rapid change in the vertical height
of the tide. At stations on a tidal river or bay the time of slack
water may differ from 1 to 3 hours from the time of high or low
water.
Toward the back of the Tidal Current Tables is an interesting
current diagram for the Chesapeake. The table lets you analyze the
best times to get out there, in relation to the current, depending
on where you're going. From it, one can devise some useful rules-
of-thumb for catching the favorable current. For instance, if
you're headed up the bay for Annapolis or Baltimore from Pax River
you should plan to round Cove Pt. at Slack, Ebb Begins at
Chesapeake Bay Entrance. You'll have following current all the way
if you can maintain about 5-6 knots. Coming back, be off Annapolis
about 1-2 hours after Slack, Flood Begins at Chesapeake Bay
Entrance. Going South from here you want to round Cedar Pt. at
about 2 hours before Slack, Flood Begins at Chesapeake Bay
Entrance. You'll get adverse current until about the Targets, and
then following all the way. Ground speed is more critical heading
south because the current generally runs faster in that direction.
You want to go as fast as possible to stay with the good current.
5-6 knots should get you to the Great Wicomico with ease. A little
faster and you'll hit the Rappahanock, Windmill Pt. just right to
catch the current shifting to take you up river. Next day hit
Great Wicomico Lt. or Stingray Pt. about 3 hours before Slack,
Flood Begins at Chesapeake Bay Entrance and you'll get a marvelous
ride on down to Norfolk, if you have some wind! But, even without
wind, you'll have it the best you can. Coming back, leave Norfolk
area at Slack, Flood Begins. Next day leave Windmill Pt. or
thereabouts about 2 hours after Slack, Flood Begins at the Bay
Entrance. Inspecting the Bay Entrance tables for any given month
will show which direction, North or South in the Bay, is favored on
any given weekend. Since we never know which way, or if, the wind
will blow, going for the most favorable daylight currents seems a
valid way to choose cruising destinations. The Tidal Currents book
seems an easier way to do this analysis than with this program.
THE MOON 1993
DATE WEEKEND MOONS
3/23 NEW 3/27-28 1ST QUARTER
4/6 FULL 4/3-4 BRIGHT, GIBBOUS WAXING
4/21 NEW 4/10-11 BRIGHT, GIBBOUS WANING
5/6 FULL 4/17-18 LAST QUARTER
5/21 NEW 4/24-25 DARK, NEW MOON
6/4 FULL 5/1-2 BRIGHT, GIBBOUS WAXING
6/20 NEW 5/8-9 BRIGHT, GIBBOUS WANING
7/3 FULL 5/15-16 LAST QUARTER
7/19 NEW 5/22-23 1ST QUARTER
8/2 FULL 5/29-30 BRIGHT, GIBBOUS WAXING
8/17 NEW 6/5-6 BRIGHT, GIBBOUS WANING
9/1 FULL 6/12-13 LAST QUARTER
9/16 NEW 6/19-20 DARK, NEW MOON
9/30 FULL 6/26-27 1ST QUARTER
10/15 NEW 7/3-4 BRIGHT, FULL MOON
10/30 FULL 7/10-11 LAST QUARTER
11/13 NEW 7/17-18 DARK, NEW MOON
11/29 FULL 7/24-25 1ST QUARTER
7/31-8/1 BRIGHT, GIBBOUS WAXING
8/7-8 LAST QUARTER
8/14-15 DARK, NEW MOON
8/21-22 1ST QUARTER
8/28-29 BRIGHT, GIBBOUS WAXING
9/4-5 BRIGHT, GIBBOUS WANING
9/11-12 LAST QUARTER
9/18-19 1ST QUARTER
9/25-26 BRIGHT, GIBBOUS WAXING
10/2-3 BRIGHT, GIBBOUS WANING
10/9-10 LAST QUARTER
10/16-17 DARK, NEW MOON
10/23-24 1ST QUARTER
10/30-31 "HARVEST MOON"
11/6-7 LAST QUARTER
11/13-14 DARK, NEW MOON
11/20-21 1ST QUARTER
11/27-28 BRIGHT, GIBBOUS WAXING
12/4-5 BRIGHT, GIBBOUS WANING