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Fin
04-07-2010, 08:33 PM
When I compare the delta tides I pull off my Navionics chip (Hotmaps, Premium, West) to the tide tables, they differ anywhere from a couple of minutes to even a half hour in time, and up to a half a foot or so. What's the deal with this?

Is it because my chip is a few years old, or something else?

ReelJerks
04-08-2010, 07:33 AM
.....Is it because my chip is a few years old, or something else?

Well since the tide on Jan 01, 2009 was different than the tide of Jan 01, 2010 as well as the moon phases, I'm thinking it MAY be the dated card. But I'm not really sure so one of the ocean guys can help you better.

:baghead:

Fin
04-08-2010, 03:54 PM
You'd think they'd put a good number of years of tides on there!!

Here's an example of the tides for Collinsville on 4/7/10:

Tide table:
2010-04-07 03:11 PDT Moonrise
2010-04-07 05:03 PDT 1.65 feet Low Tide
2010-04-07 06:43 PDT Sunrise
2010-04-07 10:23 PDT 3.01 feet High Tide
2010-04-07 13:27 PDT Moonset
2010-04-07 18:14 PDT 0.17 feet Low Tide
2010-04-07 19:36 PDT Sunset

On my Navionics Card, it showed the following:
L 4:59AM 1.9
H 10:34 AM 3.1
L 5:41 PM 0.3

AnglingWes
04-08-2010, 04:40 PM
Only being a couple of minutes and +/- 10% on level, I'd say they are pretty close. Tide Tables are configured using an algorithm to determine / predict tides. If one algorithm uses long/lat measured to the tenths ( .10 ) place and another uses to the thousandths ( .001 ) place, you will see variations in the tide tables. They are just estimates. The Nat'l Meteorological Service uses log and lat to the millionth (.0000001) decimal. The amount of processing power required to compile the data is much greater which is why most of the tables round these numbers, which skews the data.

MoMoney
04-08-2010, 05:29 PM
man I was just gonna say they are estimates and probably have different ways of figuring them and you come up with all that.It reminds me of Docs answers.

Fin
04-08-2010, 08:14 PM
It is interesting looking at the last L of the day. I can live with the other data; they are close. But there is a half hour discrepancy on the last L.

AND.....get ready for a tidal wave, folks!!

For 3 mile slough, SJ side...

High 5:31 AM 53.7 Ft
Low 5:36 PM -51.3 Ft

Be sure you don't anchor in shallow (50 ft) of water at high tide!!

Reel Fun
04-13-2010, 07:56 AM
It is interesting looking at the last L of the day. I can live with the other data; they are close. But there is a half hour discrepancy on the last L.

AND.....get ready for a tidal wave, folks!!

For 3 mile slough, SJ side...

High 5:31 AM 53.7 Ft
Low 5:36 PM -51.3 Ft

Be sure you don't anchor in shallow (50 ft) of water at high tide!!



I love fishing eerrr i mean surfing those high tides!!!!!!