Navionics tide information

[nimrod1230]

Have been idly comparing tidal information between sources and find Navionics information somewhat odd. Referring to Portsmouth, comparing with Reeds and Easytide over the last week or so dates the heights compare almost exactly the HW times are also pretty spot on but the LW times are around 50minutes behind? There is a thread questioning the existence of a rock on the Navionics chart approach to St Mallo which appears a complete mistake! Does not encourage confidence in a supposedly industry leading company. I have emailed Navionics with the query and will let you know the response.

 

[nimrod1230]

A bit anal but I’ve now had a look at some other port data and it appears Falmouth, Dartmouth are spot on correct. Dover is some minutes adrift but probably acceptable for most purposes. Southampton data is almost exactly an hour differenT both HW and LW. Also tried the data on the plotter( Navionics ) for today and although some minutes out of sink with Reeds nowhere near the error on LW times with the boating app.

 

[SiteSurfer]

BST?

 

[Daverw]

As these are only forecasts I assume different calculations will give differing results