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Mr. Squirrel

Understanding Tidal Flow - Biscayne Bay

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HELP!

This fresh water sailor is going to be spending a fair amount of time in Miami this winter and I am struggling to understand tidal flow on Biscayne Bay.  I found numerous tide charts, but I can not find anywhere that shows tidal flow direction.  I understand it is a bay so water flows in to the bay during flood tide and out of the bay during ebb tide.  My problem is the "bay" is actually open to the North, South, and East.  So the question is: during Flood tide is the water flowing North to South, South to North, East to West, or some combination of the three?

In other news, we are doing J/22 Worlds next year at Annapolis Yacht Club, so if you have suggested resources for the Severn/Chesapeake that is appreciated as well 


Thanks in advance
MS

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Dude, he's asking for data in a very general way, so I gave a very general answer.


Note that the CMAP cartridges have current vectors, presumably the PC programs do as well.  

A reasonably astute individual can take the tabular predictions and figure out the deltas and derive the basic direction of the flow.

More precise question of where to position vs state of tide requires either detailed current maps which I did not locate or as noted in the CMAP the calculation and prediction of currents based on a model. 

Assuming a J/22, the idea of a chart plotter is probably a stretch, but reviewing the CMAP PC data might be a good plan.  

 

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My experience (3 years of doing mark set / pin boat at SWC Miami) is that the tidal flows are relatively slow in the race areas inside the northern part of the bay.  (The tides are only about 30 inches.)  The depth is uniformly shallow, so what current there is is fairly uniform.

Do what the big boys do, though - no sooner than we had a mark in the water, there would be a gaggle of coaches by it, dropping current sticks in.

It's comparable to Lk. St. Clair around GPYC.  Something you might have to account for when judging a lay line, but nowhere to escape it.  Everyone is on the moving carpet.

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No kidding, but it’s a resource. He can use as he sees fit. Trying to help somebody who seems challenged to find even basics  

 

For max semi uniform currents of less than a knot, I’d probably not worry, we sail in very divergent slows on SFBay with 1 kt differences across 100 yards. 

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Do those regions have tide atlases?  The ones for Puget Sound and the Strait of Georgia are really helpful to me.  They show a lot more detail than you can get with a few NOAA current vectors.  I attached one as a sample (this the south end of Vashon on a large flood).  

For buoy racing I agree that it is even better to watch the tides effect on buoys.  

62FB831B-90E2-41A0-B3E3-3D51FDDB53A4.jpeg

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The bay is not like rivers and other freshwater estuaries and bays that are confined by land masses. Pretty consistent 10’depth and not much tidal flow. You won’t have to throw an anchor at slack tide to keep from sailing in reverse in a 10 knot tide like Jenn and the Samoan lady did in the Devil’s Triangle.

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