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Old 20 June 2014, 06:57   #1
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Tides for Lymington 26-06-2014

Hi All,

I may have an opportunity to go and play out of Lymington next week on Thursday so was doing a bit of prep and calculating tides. Usually, I'm pretty good at working out secondary tides etc, but this one has me baffled!

I have the following for Portsmouth for the day (which is the referenced Standard Port):

0338 1.1m
1039 4.3m
1557 1.2m
2252 4.5m

(all UTC, so still need converting to BST)

From the almanac, I calculated the HW offset for Lymington as -0085, giving me a HW time of 0914 UTC, or 1014 BST. I also calculated HW as 2.9m.

I was happy at this point, until I decided to verify my calculations!

EasyTide gives HW 1316 BST (2.9m)
VisitMyHarbour gives HW 1217BST (2.73m)
TidesPLanner App gives HW 1310 BST (3.0m)
Berthon Marina gives HW 1111 BST (3.0m)

I accept that tides are not precise calculations and I'm used to being out by a few minutes, but I'm seeing a difference of 1-3 hours here, which is potentially dangerous!

I've tripled checked my figures and calculations and have also checked for corrections to the Almanac, but keep coming back to the same times!

Can anyone help me to understand:

a) What the tide times will REALLY be on Thursday next week?
b) Where I've gone wrong with my calculations?
c) Why the information available online varies so much?

I've attached a scan of my secondary port calculation, in case the error is really obvious!

Many thanks,
-John.
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File Type: pdf Lymington-26062014-Secondary.pdf (124.7 KB, 25 views)
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Old 20 June 2014, 07:29   #2
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I believe this is due to the fact that Lymington will have a double high tide at Springs, so you are both right

Some sites/tables will be giving you the time of the first high tide, and some like Easytide will be giving you the second (slightly higher) tide.

You can drop down from the two maxima on the Easytide curve to see the two answers (screen grab shows UTC). Maybe Berthon Marina is doing an average?
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Old 20 June 2014, 07:33   #3
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That makes sense. It's a shame that the tidal curve for Portsmouth doesn't reflect the double high, as this might have made it more apparent.

Many thanks,
-John.
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Old 20 June 2014, 08:38   #4
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Just had another look in my almanac. Guess it's time to read the pages titled "Special Tidal Curves from Christchurch to Selsey Bill"!

-John.
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Old 26 June 2014, 12:56   #5
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Hope you had a good day!!


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Old 26 June 2014, 14:03   #6
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Quote:
Originally Posted by Crusher View Post
Hope you had a good day!!

It was great - thanks to your guidance! Didn't expect to ache this much afterwards, though...!
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