Tidal Currents in Florida Keys

We’re heading down to the Keys with our kayaks in a couple of weeks, and I’m wondering about the tides and currents. I’ve printed out tables, and tons of high/low tide pages from Saltwatertides.com. There’s a huge difference in times of high/low tides between the ocean side and the Gulf side, even when stations are only a few miles apart. A rule of thumb might be “if it’s high tide on the ocean, it’s low in the Gulf, and vice versa.”

I read somewhere that since the sea level in the Gulf is slightly higher than the seal level in the Atlantic, the current always runs towards the ocean. Is this so?

High tide on the Gulf side seems to creep from the direction of Key West to Key Largo. Any ideas about how this affect currents?

I’d welcome any advice, comments, observations, or stories. We’ve paddled there a couple of times, and I’ve been totally unable to figure things out!


I would suggest obtaining a copy of
Reed’s Nautical Almanac 2007 addition. It contains almost everything you will need to predict tide and current. While tide and current may be related they are different, just because the tide may have finished a cycle (hit high or low) it doesn’t necessarily mean the current is slack. I few weeks ago I was paddling on the bay side and there was a 2 and 1/2 hour difference between tidal flow and current. Also I would ask the locals for some information as there are special circumstances that may not be covered in references such as Reed’s.

Hadn’t hear about Reed’s
I’ll check it out. Thanks! Also, I had forgotten to download data from the current stations.

We paddle a good deal on the Hudson River, which is tidal all the way between NYC and Albany. You learn a good bit on it, but it’s easier. With the exceptions of eddies, everything thing is forced to move in a north-south direction. The river is really a fjord, is practically flat, and has practically no current generated by gravity. And yeah, the current continues well past high/low tide. We finally got that figured out!!

I’ve become really curious about this tide/current thing in general. It’s generated by the moon, of course, but how does it really work? What’s going on?

I’d thought about asking locals when we get to the Keys, but I figure they’ll be mostly powerboaters who won’t be as likely to have quite such a vested interest in currents.



We are in the Keys right now,
and have been for the past two months.

You best bet is A Garmin Map 76 GPS, which will give you the tides at the closest tide station to where you are.

The places that have the strongest currents are uually the narrowest channels and at low tide.

Prior to entering a rip that from a distance looks decent keep your skirt on anway, becuse what looks decent from a distance can be standing waves up close.

Many of the bad rips can be made worse if there are strong 20 knot east/ north east winds which will build up the waves against a out coming tide from the the Gulf.

Keep a daily check on the wind and tides and you can learn pretty quick which way to circumnavigate a Key and have the tides with you the whole way.

Have fun look for a red QCC and a Yellow one, and that will be us somewhere between Marathon and Boca Chica, (with big smiles)



GPS is OK for tides but it does not
provide current information (times speed etc.), which may be important if you need to carefully time a paddle.

…especially about those two big smiles…

Tides on flats are probably not too much of a worry unless the flats are disguising skinny water shallows -as you may know, these may strand you in water too shallow to paddle, and way too damn mucky to want to walk -and just because a bottom is covered in eel or turtle grass doesn’t mean it isn’t knee-deep oozy mud beneath the top layer of plants. Seek out local knowledge for flats.

For tides and particularly races as Jack warns about, local knowledge is also beneficial. But as you may also know, all other things being roughly equal, wide land mass separations mean slower races than constricted openings. This general counsel is compounded by whether or not there are channels cutting through a wide flat to concentrate and speed flows in a venturi-like effect, and, for that matter, what depths there are where you are paddling.

Your best bets are a series of charts and tide tables. Tealls charts, supported by ads around the periphery, are basically one-offs of the USGS charts, and are either free or cheap. I find they’re about 90% as good as the USGS ones. They’ll alert you to flats and channels

For tides, you can take a lot of the bother out of making local adjustments to main tide tables published for Key West, Marathon, or Miami, by using a site like


which presents a high number of sites all up and down the Florida Atlantic & Gulf/Florida Bay coasts. With the ability to produce both the usual tables also come the ability to produce graphs of what the tides will look like. This way, you can better estimate the race for a particular location by observing the slope of the tide curve, and plan, or be better prepared for, the tides where you’ll be paddling.

You can vary the reporting span, most of the parameter presentations, colors, and the time intervals presented on the graph. It’s a very handy place to know about.

Now it won’t answer all your questions, because it doesn’t (I don’t believe any site can) locate all places where tides (and races) may be important to know about. But it does cover a lot of sites, and allows you to better plan for tides as you, in our Fabulous Florida Keys,


-Frank in Miami

I envy you guys—
down there in South Florida! Oh, weeeell, it won’t be toooo much longer.

I never had thought about any possible connection between the slope of the tide curve and current speed. I’ll have to toy around with that idea! So far, I’ve only printed out lots of tables. I really like tbone because it links you into mapquest, so you can easily find out where the individual tide stations are.

We already have a collection of USGS charts—the paper ones. I throw them into the scanner, print out what I want (8 1/2 by 11), tape two of them back to back, and have them laminated. It works well; sometimes I draw in additional topo lines and stuff.

The latest thing this year is Google Earth. It’s awesome! I’ve been printing out birds-eye views of the areas where we’ll be paddling, and will have them laminated like the charts. I’ve discovered that the images download as jpeg files, and you can throw them into photoshop and fool around with stuff like comtrast and sizing. It makes for wonderful printouts, especially if you use photo paper.

Still, I’ll be wondering about what and how and why the water does what it does, until I get it figured out. If I ever do!

Sounds like you’re in our area, Jack. Big Pine Key—and yeah, with big grins. We’ll be the ones with the noisy grandkids, so I’m not so sure anybody else would want to hang with us! The little ones won’t be going out in the kayaks, though, just the oldest grandson, so I don’t expect to do as much paddling as we would have otherwise. When we’re out, we’re the ones with as many as 4 yaks; two white, and two yellow.

We do have a VHF radio, and use it mostly to keep a check on the weather. We go hide somewhere if the wind is over 15 knots! We poke around somewhere that’s sheltered; we’ve been out just enough in winds blowing against currents to have a healthy respect for what happens.

Any stories?



Serious currents
Many years ago a buddy and me spent a month camping on one of the Florida keys. One day we rented a small aluminum fishing boat (12 or 14’) with a ten horsepower motor to go out fishing. We were young and from New Mexico and didn’t know anything about ocean currents so didn’t even think about them. Anyway we motored out about a couple of miles from our camp on one of the larger keys to a good fishing spot between it and the next key. When we went out it must have been between tides because there was next to no current. However after fishing for several hours we noticed that our anchor rope was quite tight and the sea was moving quite quickly around us. We decided it was time to go back in. We could barely raise the anchor because of the current. We finally did and headed in, and I have to tell you that the trip back was the scariest 2 miles I ever traveled in my life. The current in the main channel was like a large fast river with standing waves which were coming super close to breaking over our stern. To make matters worse we kept seeing large shadows pass under our boat which of course we believed were probably sharks. We made it back by the hair on our teeth and learned a good lesson. It scared the s–t out of us. Looking back I do not believe even a good kayaker could not have made any headway against that current, and would have been challenged to even cross it.