Tide Time

essexboy

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Might seem a silly question, but when is it officially high tide ? Is it when the water first peaks, or half way through the high period ?
 
Depends on where you are. If you are in a place where the tides rise and fall equally (that is most places), high tide is the time when the water is at its highest on that tidal cycle. In some places (Poole for example) the water does not rise equally so there are two "high" points each cycle, so you have to refer to the tidal curves to determine when it is at its highest.
 
In some places (Poole for example) the water does not rise equally so there are two "high" points each cycle, so you have to refer to the tidal curves to determine when it is at its highest.

...and Reeds have pretty much given up on the whole concept, and refer to tide times in Poole by low water instead :)

Pete
 
It's easy, high tide in Poole is when you don't need to get in/out of Parkstone Bay Marina and low tide is always at the point when you need to get back, but can't because there's no water.
 
...and Reeds have pretty much given up on the whole concept, and refer to tide times in Poole by low water instead :)

Pete

So is Southampton! It is because of the double high that low water is shown as the base. In fact the whole of the Solent's tidal curves are based on low water apart from Portsmouth.

But then the OP is based in Essex, so none of the above applies. In truth the high water time is an approximation and the time shown is the mid point of the high water hours. So you need to look at 1/2 hour before and half after to get the high water hour and move on from there.

If you use the tidal curve then then it is split into 10 minute segments and gives a slightly more accurate prediction. But remember that there are other factors which effect tidal height - pressure and or wind.
 
...and Reeds have pretty much given up on the whole concept, and refer to tide times in Poole by low water instead :)

Pete

Yes, but did not want to confuse even further. Easytide and our local tide tables give the two high tide times and low water. Non Locals are also confused by the second "high" being lower than the first on springs! Makes it easy working out when to go alongside the wall to dry out as on springs the first high is bigger than the second and comes up very quickly. So you can go alongside at night and float off before it gets busy the next morning - but it does mean a small window around dawn to do the scrubbing.

You soon get used to it and use low water as the consistent reference point.
 
Might seem a silly question, but when is it officially high tide ? Is it when the water first peaks, or half way through the high period ?
Leaving aside the double high tides in the Solent, the question is actually based on a false premise. There is no high water "period", because high tide exists only for one instant in time. The water level is lower than the peak (a mm or so) a minute before and a minute after high tide, and is at its peak only for an instant, midway between those two times.

The high water time stated in tide tables is a best-efforts prediction for when that instant will occur.
 
So is Southampton! It is because of the double high that low water is shown as the base. In fact the whole of the Solent's tidal curves are based on low water apart from Portsmouth.

Sorry, yes. I was thinking of the fact that they don't even print high water times in the Poole table. They have a height, but the times are blank.

Pete
 
If you read your Reeds almanac it will tell you what time is being predicted. It might say the middle of the stand, ie. the middle point of high water. It might say the time is for the start of high water and then give you a stand time, ie the time water remains high before starting to lower.

Other times it might refer to a double high water and then say the predicted time is the peak of the first high water, mid point between the 2 peaks or whatever.

As you can see from the answers given on the thread thus far it depends, so important to have your Reeds almanac on board and to use it.

Forgive me if I'm teaching my granny to suck eggs but the almanac will also give tidal curves which allow you to predict exact heights at any given time. Usually the curve is shaped like a mountain based around high water but sometimes it is shaped like a trough based around low water.

For a very rough fag packet calculation of tidal height you can use the twelths principle. Work out the tidal range between high and low water, let's assume 4 metres. Divide by 12 = 0.3 metres then allocate those segments as follows: 1 segment, 2 segments, 3 segments, 3 segments, 2 segments, 1 segment with each gap referring to 1 hour of time. So 2 hours after high water you would be 1+2=3 segments lower, or 0.9 metres in this example. It's only an approximation and always best to use the tidal curves but it gives you a rough idea.

Once again sorry if the rather long winded post is stating the obvious but someone might find it useful :)

Henry :)
 
Sorry, yes. I was thinking of the fact that they don't even print high water times in the Poole table. They have a height, but the times are blank.

Pete

They do in Easytide and our local printed tide tables which are from the UK Hydrographic Office. Some tables just use the times, other print out the tidal curves. Both have their uses. You can download Easytide tables and curves all in the same document.
 
They do in Easytide and our local printed tide tables which are from the UK Hydrographic Office. Some tables just use the times, other print out the tidal curves. Both have their uses. You can download Easytide tables and curves all in the same document.

In practice I mostly use the Imray tide app on my phone. Just interesting that the Poole curves are so abnormal that Reeds don't bother printing high-water times in their almanacs.

pete
 
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It's easy, high tide in Poole is when you don't need to get in/out of Parkstone Bay Marina and low tide is always at the point when you need to get back, but can't because there's no water.

No such problem at Cobbs Quay , although you might be delayed by up to half an hour due to the two bridges -depending on your airdraft.
The revised lifting schedule introduced from October 1 should reduce the delay - to be fair the bridges have not caused me much of a problem this year.
 
To be honest, I'm thinking about Cobbs vs Parkstone Bay. A friend has his Trophy 21 on dry dock at Cobbs. I've not tried but I should be able to get under the bridge as long as I drop the frame that holds the bimini at the back of the boat. As long as it's not too difficult navigating between the boats holding station waiting for the bridge it's a possibility.

I quite like South Deep at Parkstone once we've got the boat away and Cobbs doesn't seem to be as good in this regard. And I like all the guys at Parkstone Bay - a great bunch and very helpful. But the fact you almost always seem to have some water underneath you is a big bonus, and it's quite a bit cheaper at Cobbs.

Dry berthing in Poole seems to be a bit of an issue. Not may marinas seem to offer it. Salterns is expensive - no dry berth but well located. Lake Marina looks nice but no dry berth (to my knowledge) and parking is awful. Cobbs looks good but the bridge puts me off. Poole Quay Boat haven is expensive all year round and no dry berth. There always seems to be a compromise somewhere!
 
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