Tides are off significantly from chart app right now. At 4’, was actually 2’6” off the Wando. Has been that way since at least Saturday, and wind direction has been out of S and N, so that doesn’t appear to be the reason.
Which one are you reffering to?
I use Tides and WillyWeather apps and also Simrad on my boat which all sync up. But they don’t reflect actual tides rn for some reason.
I cant tell if mine is off or not. I do know that the Tides app is owned by the same guys that own CF… maybe they could chime in with some info?
Ill try this… paging Mr @snickers , can you fill us in on anything? I havent seen em around in a while but maybe this will conjure him up though.
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If you google “Why is my tide chart not accurate” its layed out pretty good.
Basically they are planned out and predicted astrologically, so the stuff right along the coast is usually pretty good, ,taking into consideration fetch, pressures, and whatnot. That stuff is easy to predict and get it close enough for “government work”.
The stuff in the rivers and creeks is a whole other thing, in that things like strong winds, rain upriver, even high and low pressures will effect the actual tide vs the predicted tide much more inland.
Hope that helps and yeah where is @snickers anyway. Its almost mahi season, he’ll be by any time, lol.
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Work has been absolutely killing me lately - sorry that I have been missing.
Mahi season is going to be so good, you are correct that I will be here!
@EF1 is spot on with his description. In addition to this however, the datum that you are viewing can result in the levels not matching. When we predict tides, we take water measurements in reference to something fixed like a bridge or landmark. Then we take those numbers and reference them to a datum so they make more sense. Typically in the US we view tides in the MLLW (Mean Lower Low Water) datum, which means all of the heights are in reference to the average of the lowest low each day over the last 10-15 years.
If you are using our tides app, try adjusting the chart datum to MLLW on the settings page to see if this helps.
Otherwise if you give me the station name, and what you are comparing our predictions to, then I can have a look at it.
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https://tidesandcurrents.noaa.gov/waterlevels.html?id=8665530
wind has killed us the last couple days, started N on the left hand side and has been absolutely honking E today, opposite effects for the bigger parts of this system
predicted vs observed overlay is very helpful in knowing which sandbars you’re gonna clear today
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It’s times like these that I love this forum.
Thanks for the generous details fellas
If you wanna mentally fall off the edge of a flat map, search up “amphidromic nodes” around which tidal amplitudes circulate
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is that like way up the dawhoo or cooper, into the brackish stuff?
I cant wrap my head around where else a tidal node would be.
edited…never mind, I got it now. god loves a good googler. that was a good read
Very interesting, thanks! Couple questions. So looks like the timing of high and low aren’t that affected, but the amplitude between can be? Also, further away from the harbor, up the rivers and into the shallow creeks, are the tide swings greater?
I think the semidiurnal periodicity and fairly large amplitude of our position in this node is forceful enough to pretty much stay on schedule aside from extreme events
BTW the reason Beaufort has way bigger tides than us is because it’s farther from the center of our node
USVI has like 6" tides, it’s like groundhog day and it drove me nuts
IDK about up skinny creeks vs big water, I’d imagine it can be more or less dramatic depending on the direction of flow and wind in the narrows. wife’s grandfather knew stuff, and he said the summer sea breeze right at the coast would wait till the tide switched in the morning, won’t blow till the water moves too
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Wife’s grandfather was right
I thought everyone knew that