Easytide inaccuracy?

[ex-Gladys]

Haven't posted in a while, mainly due to Gladys being OOC following a T-bone im Mersea Week last year. However.... Went out this weekend and on Saturday assumed I'd got the tide time wrong, as Easytide was quoting c.1000 High, and my mark 1 eyeball thought it was more like 11. Assuming I'd made a Daylight Saving error, I checked for Sunday and it should have been 1109. We had our first under sail trip for over a year and took the flood from Mersea, up the Blackwater planning to get as far as we could on the flood before coming back down witht he ebb.

We turned at the Doctor at around 1100 and then proceeded to punch the flood all the way back down to Stone...

Answers on a postcard please....

 

[TigaWave]

cmap says 10.46 and 23.15 at Osea island on saturday? and 11.02 at Bradwell waterside, so it would appear the eyeball was working correctly.

 

[tillergirl]

Mornin' Larry

High Water Heybridge on Saturday was 10.54 BST according to the local tide tables. Sunday 1153. Best throw away Easytide!

 

[ex-Gladys]

Mornin' Roger,

Saturday the obs was on the mooring, Sunday was whilst sailing, and I know I didn't check anything other than WM times. There is a fairly significant change difference going west in the Blackwater....

 

[Superflid]

I've noticed that Easytide is often up to 40 mins out compared to eyeball/tide tables at Boston.

 

[rwoofer]

A couple of weekends ago I experienced it being at least an hour out on the Hamble. I put it down to misreading the time incorrectly on two successive days.

Hopefully this confirms that I'm not going prematurely senile.

 

[ex-Gladys]

The one that particularly got me was Saturday, when I sat on the mooring doing some odd jobs, expecting the boat to swing and it didn't for an hour. Obviously I can't check back on the Easytide time, but 1000 won't have been far out as it was 1109 Sunday... The old girl didn't swing (nor did anyone else) until near enough 11

 

[morgandlm]

I use Easytide for Bradwell. There is a considerable lag in HW for Osea or Marconi (20 + mins). I have never noticed a major discrepancy with Easytide but have been caught out by high pressure affecting tide height when calculating depth for getting back into Bradwell.

Remember the time given for HW is strictly speaking defining a state half an hour before and half an hour after the given time. Air pressure and wind direction can also influence.

I picked up a mooring off Marconi today and my boat had not swung 40 mins after HW Bradwell but I was in slack water by then.
Morgan

 

[damo]

We use Belfield for calculating lock times at the marina, and find that their algorithm is just about spot on for spring tides, but may be up to an hour and a metre out (tide is usually ahead of prediction) on neaps.

It is sometimes a bit nerve-wracking when a boat is trying to make the last lock of a tide, and the level on the cill is dropping quickly.