Tides along the French/Belgian/Dutch coast

[Cantata]

Picking up from a comment by 'benw' in the '1st time to Ostende' thread...
Having been over there quite a few times, and coast hopped using Blankenberge, Oostende, Dunkerque, Niewpoort, Gravelines at various times, I always carefully worked out tide times usually using the Reeve-Fowlkes (sp?) atlas, and noticed that the tide ALWAYS seemed to turn about an hour earlier than I predicted.
This became an obsession as obviously I thought I'd messed up with the extra hour, but my calcs always seemed to be correct.
Anyone else noticed this?
I looked at one of those 'dial-up' tidal stream predictors that Benw mentions, and used it quickly in the chandler to rework the previous calc I'd done, and the gadget got the turn of tide absolutely right, where I had not.
To my regret I didn't buy it (it wasn't that cheap) and I haven't seen one in a shop over there since. I remember it was made in UK and branded 'Roberts Charts' or Roberts something else. Interesting to hear that they are still available (unless Benw bought the last one....).

 

[AliM]

Is it simply that the times are local, where you are used to using UT, or that they use (or don't use) LT inc. daylight saving time? We got very confused when trying to use the UK almanac for the NL coasts - we worked out what they were doing eventually, but it didn't seem at all logical.

The solution is simple - buy the Dutch tidal atlas - someone will tell you the proper name shortly. It's published every year, and has the tidal heights at main ports along the Belgian and dutch coasts, hour by hour, and detailed charts of teh tidal streams, hour by hour. It's incredibly easy to use, even for the complicated tidal calculations in the shallow bits, and it costs about 15 Euros. You should be able to identify it by the big piles of them in every chandlery!

 

[Cantata]

Is it simply that the times are local, where you are used to using UT, or that they use (or don't use) LT inc. daylight saving time?

No, that's the obvious thing that I thought but I am certain I was doing it right.
I did start to wonder if the Reeve-Fowlkes was actually wrong for this coast - mind you it is shown in extremely little detail.

 

[Jomo]

I always carefully worked out tide times usually using the Reeve-Fowlkes (sp?) atlas, and noticed that the tide ALWAYS seemed to turn about an hour earlier than I predicted.

Yep, I've been using that 1 for about 4 years, and I seem to get the tides wrong by an hour, always assume I've made a bodge, and now triple check using other systems. Getting to the point of thinking of trying another tidal flow atlas

 

[tillergirl]

Just faintly possible that things have changed. A couple of years back, a chum and I was independently calculating dropping down from Calais to Boulogne and coming up with quite different results. In the end, the very last thing we checked were our Admiralty Tidal Stream Atlas' and his - the later edition had some quite different data south of Gris Nez - and no Dick mine wasn't the 1940 edition!

 

[Athene V30]

Leaving Calais the other day I was expecting to just get the start of the NE stream but it was already running at 1+kt.

The previous day I left Brighton early on the tide aiming to catch the start of the E flow off Beachy Head (and then carry all way to Dover) but I didn't get a fair tide until Dungeness. That is why, as I had fair tide left over, I ended up in Calais and then Gravelines the next day rather than Dover or Ramsgate!

 

[dt4134]

The Reeve-Foukes Atlas references everything to Cherbourg. I doubt that the relationship between tides at Cherbourg & those in the Southern North Sea is a simple as had to be assumed to make his method work.

There's a similar problem with the Reeds Almanac which references Irish Sea tides to Dover. I certainly identified one case where this was out by a whole hour because the assumptions about the relationship between HW Dover and the loacl primary ports HW just didn't work that day. The tides worked as predicted if you used tidal diamonds but the other boats (it was a race) using Reed's were caught out.

 

[Artemis_C2121]

Having just come all the way down the channel (now in Guernsey) I picked up a local tide info and used it for my calculations all worked spot on I did cross ref it to reeds and got the same results , However I agree with JCP that basing info for the southern north sea or the Dover Straights from Cherbourg is not going to work.

After sailing in the one area for so long its strange to see that heading west the time of HW just about stands still as you advance down the coast makes for interesting calculations came from Cherbourg through the Alderney Race on Sunday which was on calculation I needed to get right and felt quite pleased to see the mass exit from Cherbourg heading west at the same time as us.

 

[MoodySabre]

Anybody want me to get a Dutch tidal atlas when I go back there next week? (assuming I go somewhere with a chandlers).