For boaters trekking to The Bahamas for the first time, the Gulf Stream can seem like the most intimidating stretch of ocean imaginable. It is, after all, one of the most powerful forces on earth, churning billions of gallons of seawater out of the Caribbean and shooting it toward Europe at up to three knots.
But, once you’re out in it, you quickly realize that it’s not that much different than any other bluewater passage. There’s quite a lot of magic to flying across the Gulf Stream, with water so blue and crystal clear that it seems to go on forever. The way the shafts of light play through those waters can be spectacular, and if you’ve got lines in the water, you might be in for a real treat. If you’re headed north, the current is like a magic carpet ride, boosting even the slowest sailboats to almost 10 knots.
Here’s a look at how to plan for and execute a safe crossing of the Gulf Stream from Florida to The Bahamas. We’ll cover how to do it, where to do it, what weather is right and wrong, and other considerations you need to know.
How to Cross the Gulf Stream to The Bahamas
Because of the Gulf Stream’s north-setting current, most cruisers will make as much southing as they can along the US East Coast. From South Florida, it’s one more day hop across the Gulf Stream to the first islands of The Bahamas. This is the typical snowbird cruising route, as described by Van Sandt in A Gentleman’s Guide to Passages South. It allows for staying in the ICW or limiting travel to day hops on the outside.
The general advice is to get as far south as possible before crossing. The farther south you can get, the better your ride across the Stream will be and the more options you’ll have. The slower your boat, the more impact that has. For example, if you’re coming from Key Largo, you could depart with a moderate southeasterly breeze — not an uncommon forecast. You’d also have a heading that allows you to go with the flow instead of fighting against it, which is another plus.
I’m borrowing the terms of crossing zones from Chris Parker at Marine Weather Center because this defines the forecasts. Even if you don’t use his services (which you should be using, by the way), you’ll come across these distinctions. The two zones are the North and South Crossing Areas.
North Crossing Area
The north crossing area is roughly defined by a straight line between West Palm Beach (Lake Worth Inlet) and West End, Grand Bahama. This track is roughly 56 nm due eastbound.
However, there are various departure points across the zone. Many boats depart from points farther north, like St. Lucie Inlet or Fort Pierce Inlet, and cross into the Banks, heading straight for the Abacos.
Alternatively, boats can cross from the south after leaving Miami or Fort Lauderdale for a straight shot into Grand Bahama or the Abacos.
Once you are on the southwest corner of Grand Bahama, it’s an easy bluewater passage through the Northwest New Providence Channel to head toward the upper Berry Island or Nassau.
South Crossing Area
The south crossing area is basically Fort Lauderdale or Miami directly to Bimini. It’s about 46 nm due east from Key Biscayne in Miami to Bimini. This is the shortest crossing from Florida to The Bahamas.
Other routes include departures from Key Largo (or anywhere in the Florida Keys). You can make landfall in the Bahamas at Bimini or cross onto the Great Bahama Bank south of the Bimini Islands near South Riding Rock. This route leads you toward Andros, the Berry Islands, or Nassau (and then the Exumas).
Or, you could continue into the north crossing areas for landing on Grand Bahama.
Gulf Stream Crossings From the Carolinas
Boaters who want to take a shortcut by bypassing Florida can do so, but it requires a two or three-night passage. Marsh Harbour in the Abacos is approximately 490 nm due south of Beaufort, North Carolina, and about 400 nm south-southeast of Charleston, South Carolina.
You don’t hear as much about these routes, but people are sailing them all the time.
Chris Parker and other weather providers do not provide a specific marine forecast for this passage. Instead, it’s up to you to anticipate the location and weather conditions you might expect en route. The good news is that crossing the Stream is a very small part of the passage, and once you’re out of it, it’s an easy blue water passage down to the Abacos.
Getting Gulf Stream Location Information
Like the Jet Stream in the upper atmosphere, the Gulf Stream moves around a little. It’s always there, but it might start a mile from Palm Beach one day and ten miles offshore another. It might be only 2 knots one month and 3.5 the next. It’s at its steadiest and strongest off of South Florida but varies and wobbles more the farther northeast you go.
My favorite app for viewing the forecasted position of the Gulf Stream is windy.com. By activating the “current” layer, you can spot the Gulf Stream easily moving north from the Florida Straits.
You can select a point on the map from the Windy website and get the latitude and longitude. This lets you get waypoints, which you can input into your navigational chart app for reference. Then, you’ll be able to make your plans accordingly.
For example, looking at the coast of Florida, I might want to know how close to shore I need to be to avoid the Stream when sailing southbound. Looking at the map, I can see that the western wall of the Gulf Stream is more or less due north-south. By clicking and getting that location, I can see that the wall is at 080º West longitude.
As is the case with all global forecast models, it’s best not to get carried away with the details — it’s not going to be precise to the mile. But it will give you a very good idea of what to expect.
Beyond using Windy (or another app that shows similar information), a professional weather router like Chris Parker can provide specifics for your trip, including recommended points where you should enter and exit the Gulf Stream. In South Florida, the NOAA marine zone forecasts usually include the distance offshore of the western wall of the Gulf Stream.
Characteristics of the Gulf Stream
The Gulf Stream is often described as a northward-flowing river. However, it’s harder to visualize than that because it moves around like a river with no banks. Its point of peak current, called its axis, also shifts around.
Leaving the coast of South Florida, the current will begin to pick up rapidly. Off of Palm Beach and Miami, the current almost always sets due north. By the time you’re ten miles offshore, the current is usually quite noticeable. It progressively strengthens until you reach its maximum as the current’s axis. This is important because as you plan your navigation, you will not get 3 knots of current for the entire trip. It’s more of a bell curve, with a little current when you leave that builds up to 3-3.5 knots, and then it slowly decreases until it’s back down to nothing, and you’re in The Bahamas. Over the course of the whole passage, it averages out to be 2 or 2.5 knots of current.
Beyond the set and drift caused by the current, the Gulf Stream has markedly warmer water than the surrounding areas. This is a driving force in Gulf Stream weather forecasting because it provides lift for squalls to form quickly. The power of this warmth also moderates the entire European continent’s weather—a giant heat pump moving energy from the Caribbean to the high latitudes of the English and French coastlines.
Weather in the Gulf Stream — Why Is Crossing the Gulf Stream Dangerous?
Here’s where crossing the Gulf Stream can get exciting. For the most part, it’s like any other stretch of ocean. But when the wind opposes the north-setting current, it’s like any other river or tight inlet with a lot of current: things get messy.
The force of the water moving northward and wind blowing southward causes the waves to pile up into “square waves,” meaning they get very steep, have a very short period, and break very quickly. This uncomfortable and potentially dangerous condition pops up quicker than it would elsewhere. So, while 10 or 15 knots of wind doesn’t sound much, it can make for a brutal ride in the Gulf Stream if it’s coming out of the north. If it’s coming out of the south, conditions will be lovely.
You also have to consider that forecasts tend to underestimate the wind speed in the Gulf Stream. The warm water changes things locally; the Gulf Stream is powerful enough to make its own weather. So, if your app says it’ll be 10 knots from the north, you shouldn’t be surprised to find it’s 15 gusting to 20.
Likewise, sea conditions are poorly forecast when the wind is out of the north. There are no weather buoys in the crossing zones, only on each side. So, the weather models (and the rest of us) have little information on which to base our estimates. The NOAA zone forecasts off South Florida are about the most accurate forecasts available because they are written by actual forecasters familiar with the area. Using your weather app, you need to consider worst-case scenarios (and maybe even add a little bit to that).
The general advice is to never depart on a Gulf Stream crossing when the winds have any northerly component (NW, N, or NE). This will keep you out of trouble when it comes to sea state. There’s very little gradient wind during the wet season (summer) in Florida. Finding a calm day to motor across is seldom a problem. Expect afternoon squalls in the Gulf Stream during summer, especially on days when they are present over Florida.
During the dry season (winter) in Florida, the prevailing gradient winds blow out of the east or southeast. This makes for a rough crossing that most small boats don’t want to attempt. Large motor yachts do it all the time, but the rest of us are forced to wait until the right weather window appears.
What’s the right weather window for crossing the Gulf Stream? The goal is to plan a crossing when the wind is in a favorable direction or calm enough to cross.
The most favorable direction would be from the southwest to west, but this only happens on one condition in South Florida — with the approach of a cold front. If you watch the weather, a cold front will approach, and winds will begin to relax as they clock south, southwest, and west. This provides a window during which you can cross, but you will only have 18 to 36 hours to do so (depending on how quickly the front is advancing). Note that this strategy is used by both sail and motor vessels to ensure a smooth ride. No one likes bashing into the seas, and a southwest-west wind enables you to cruise with ‘fair winds and following seas.’
Once the cold front hits, thunderstorms and strong northwest to north winds will blow for a few days. You definitely want to be out of the Gulf Stream and in a safe harbor when that goes down. The weather after the cold front is exactly the worst conditions you want to avoid in the Gulf Stream: squalls and strong northerly winds.
Instead of crossing in front of a cold front, you could wait for the gradient winds to relax. As winter progresses, this gets less common, and pressure systems tighten between winter storms up north and advancing cold fronts. Still, it’s not unheard of to have a few days of light and variable winds that make for a good motoring crossing.
When it’s time to head home, the same tactics apply. But this time, since you’re heading westbound, the prevailing east and southeast winds help you out. This means it’s usually much easier to find a window to cross home than it was to find one headed east.
Tactics for Crossing the Gulf Stream in a Small Boat
Now that you have an idea of when to go, it’s time to examine the mechanics of how it’s done.
Just as a quick recap, let’s review some of the basics of GPS figuring and boat handling.
- Heading — The direction the boat is pointed
- Course over ground (COG) — The line over the ground that you’re moving
- Speed through water or boat speed — The speed of the boat pushing through the water (measured only by paddle-wheel speed log or pitot tube on your instruments)
- Speed over ground (SOG) — The actual speed you’re making across the ground (measured only by GPS)
Over the years, I’ve seen three techniques for crossing the Stream, each with pros and cons. The method that works for your boat might not be the best for another, i.e., a sailboater’s method is probably overkill for a sportfisher doing 40 knots.
Captain iPad’s Technique — Just Follow the Line
Captain iPad makes the Gulf Stream crossing like he does everything else by selecting his destination on the iPad or chartplotter and hitting Goto or Direct. A straight line is drawn, and the autopilot is set. If he’s even more techy, maybe he uses the autoroute feature. Done!
Well, for the Gulf Stream, there are a few problems with that. We know that the boat is going to be set north, so the autopilot (or captain) will have to continually increase their correction by steering south. In a go-fast, this is fine. But in a slow boat, every degree you turn more southerly will reduce your speed over ground a little. By the time you’re in the middle of the Stream, you might be heading 170º with a course over ground of 095º, but your speed over ground is now down to less than 2 knots, maybe less if you’re really slow because it’s really rough. Now, you’ve put yourself out in the worst part of the Gulf Stream for twice as long by halving your speed! Yikes!
I’ve Done It Before’s Technique — Do a Little Planning
After just following your iPad or chartplotter and having a bad experience, Skipper ‘I’ve Done It Before’ thinks he’s outsmarted the system. This time, they will put in a little bit of correction to ensure they get to the right place.
The idea is simple: by adding a bit of southing to your straight-line course, you will split the difference and not have to make such a huge correction in the middle of the stream. Once you’re past the Stream’s axis, you can allow the GPS to steer directly to your destination.
This hybrid approach lets you avoid relying on your chartplotter for navigation, but you just make sure it doesn’t make an over-correction in the middle that slows you down.
Salty Seadog’s Technique — The S-Course for Sailing Across the Gulf Stream
The S-course is the most reliable way to plan a Gulf Stream crossing for slow boats and sailboats. It allows you to steer a constant heading during the entire trip, which is great news for a sailboat if that heading allows for a beam or broad reach and nice sailing.
This technique for slow trawlers or motoring sailboats means that your speed over ground will be more constant during the trip, making your planning easier.
Here’s how it’s done. First, you must assume a few facts about the dynamic Gulf Stream (which you can fine-tune as needed). Generally, we assume it’s northerly (360º) with a total average of 2 or 2.5 knots. By calculating how many hours you will take to cross, you can tally the total amount of drift the current will cause.
Then, you draw your course to your destination. From the destination, make a vector based on the set and drift of the total current you’ll have over the trip. From this, plot your heading to steer.
On the water, you’ll maintain that heading over the entire course, and the result will look like an S on the GPS, which will end at your destination.
Obviously, in the age of GPS, you can monitor it along the way. Once you see the effects of the Stream waning, you can fine-tune your heading for your intended landfall. But hopefully, it’ll be close (it’s fun to see how close you can get!)
Gulf Stream Decision-Making for Boaters
While sitting in Lake Worth or No Name Harbor, you’ll undoubtedly come across fellow boaters planning to make the same crossing as you.
Buddy boating across the Gulf Stream appeals to many, especially first-timers who have met more experienced cruisers. The camaraderie can be enjoyable, and everyone is happy to get tips and pointers from those who have plied these waters before. But it’s important not to fall into the trap of allowing another boater’s planning and decision-making to alter your own — just because they think an upcoming weather window looks good does not make it a good one for your crew.
It’s very important to check your own forecasts, do your own research, and plan your own trip based on what you and your crew feel comfortable with.
It’s never a bad idea to wave off and wait another day. In aviation, we have a say. “I’d rather be down here, wishing I were up there, than be up there wishing I were down here.” The same idea applies to boating. We’re recreational boaters; there’s no reason to put the recreation on hold and beat ourselves and our boats up.
It’s always disappointing to see other boats posting photos from the other side before you make it, but there’s nothing wrong with hanging out in Florida a little longer until the weather is more favorable. Even if it doesn’t feel like it sometimes, the weather will change, and there will be good crossing windows in the future.
Dealing with Ships in the Gulf Stream
After so much research (and lengthy articles like this), the actual crossing is usually rather anti-climatic — if you’ve done it right, at least.
However, one factor that surprises first-timers is the amount of shipping traffic they will encounter in the Gulf Stream. It turns out that commercial ships like that 3-knot speed boost just as much as the rest of us. The result is a pretty endless stream of ships northbound. It’s the preferred route for anyone leaving the Panama Canal and bound for the US East Coast or Europe (so, basically half the world!).
First, if you don’t have AIS, the Gulf Stream will make you wish you did. The ships, and most cruisers for that matter, will have AIS that will include their COG and SOG. The chartplotter will calculate and tell you your CPA (Closest Point of Approach), which is a huge help when deciphering which direction the ship is traveling and how much space there is.
The problem is two-fold. First, the ships usually move between 15 and 20 knots — so relatively fast. Add in the corrections we’re all making for the current, with our heading not matching our courses, and it becomes confusing quickly.
On night crossings, you need to be up to date on your lights. It can be challenging to figure out the lights on a cruise ship and which way it’s going.
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