Techniques & Tactics
- Category: Techniques & Tactics
- Created: Wednesday, 22 September 2010 00:00
- Written by Charles Doane
Thousands of vessels sneak past Cape Hatteras each year without mishap, but you should never assume its reputation as the Graveyard of the North Atlantic is undeserved. To get an idea of how dodgy a place it can be, you need only contemplate the fate of the various nav aids that have been stationed at the end of Diamond Shoals, which jut out some 13 miles beyond the cape itself.
First came a 320-ton lightship, which the federal government anchored on the shoals in 1824. It lasted three years before being driven like driftwood on to nearby Ocracoke Beach in a massive storm. There followed a series of floating buoys, the lifespans of which were notoriously short. Then, in 1890, a permanent light station was erected, but was obliterated before it was completed. In 1897, another structure was built, but it survived only two years before being destroyed by a hurricane. Its replacement, another lightship, was torpedoed and sunk by a German submarine in 1918.
The government has since obviated the threat of submarine attacks, but Hatteras itself is just as dangerous as ever. The total number of shipwrecks in the area is not known, but the fact that estimates range from around 600 to over 1,000 should inspire provocative nightmares in the mind of any cruising sailor planning a southbound passage through the area in the fall or early winter.
The reasons for all the mayhem are well understood. It is here, right at Cape Hatteras, that the Gulf Stream, probably the single most significant climatogical feature on the face of the planet, suddenly kicks east away from the American continent and begins splaying about the North Atlantic like a loose firehose.
The quantity of water involved is enormous. Where the Gulf Stream flows through the Straits of Florida at 30 million cubic meters per second, off Hatteras it flows at a phenomenal 80 million meters per second. This compares to only 0.6 million meters per second for all rivers flowing into the Atlantic, north and south, including both the Mississippi and the Amazon. The speed of the Stream off Hatteras is 3 knots or more, and this always creates ugly wind-against-current situations whenever the wind blows from anywhere between north and east. Particularly in the shoal waters around the cape, the waves generated are guaranteed to be steep and treacherously close-packed.
The sheer physical force of the Gulf Stream off Hatteras is one thing; the warmth of the water is another. This is what helps make the cape such a self-fulfilling prophecy of doom--a place to avoid in bad weather that makes its own bad weather. For here at Hatteras that the warm Gulf Stream also confronts the weaker southbound Labrador Current bringing cold water down from the Arctic. The temperature gradient is quite steep. Where water in the Stream just past Hatteras is typically about 78 degrees F, the water immediately west of the Stream as it leaves the continent can be 20 degrees colder or more in the fall and winter.
This huge difference creates unstable weather locally. Also, as cold fronts trailing behind deep low-pressure cells far to the north sweep off the continent, the frigid air behind the frontal boundary is suddenly heated and starts rising as it encounters the warm Gulf Stream at Hatteras. This often creates a secondary low-pressure cell within the front that can quickly generate gale-force winds. Sometimes in the fall and winter the strong thermal field between the cold continental air and the warm Gulf Stream causes very strong coastal lows to form in the Hatteras area independent of any inland weather system. These Cape Hatteras lows, or nor’easters, then sweep up the Eastern seaboard, pummeling the coast with northeast winds that sometimes reach hurricane force.
Plan A: Take the ICW
Given all this unpleasantness, many cruising sailors prefer to have nothing to do with the cape when migrating south in the fall. Fortunately, the government was not just twiddling its thumbs while lightships and light stations were being devoured on Diamond Shoals, but was also busily constructing the Intracoastal Waterway (ICW). Currently, more than 13,000 recreational vessels enter the ICW at Norfolk, Virginia, each year and safely pass well inland of Hatteras along a charming run of canals, tidal creeks, and open rivers and sounds that stretches approximately 180 miles to Beaufort, North Carolina.
If your boat draws 10 feet or less and has a masthead height of under 65 feet (the standard vertical clearance under fixed bridges on the ICW), this is definitely the safest way to go. Its only drawback is when you are pressed for time, for this inland path is both intricate and complex. There are many opening bridges to negotiate, and one canal lock, at Great Bridge, Virginia, just south of Norfolk. Once clear of the Albemarle and Chesapeake Canal, there are then numerous places all the way down to Beaufort where boats drawing 6 feet and more will quickly be aground on wandering more than a few yards from the dredged channel.
I have twice seen professional delivery crews running yachts on the ICW at night, but I would not recommend this to anyone who is less than perfectly competent. This is definitely not a plug-and-play autopilot trip. Ideally, you want to have one decent helmsperson, plus another crew conning the boat from marker to marker, on deck at all times. At a minimum, you’ll want one very good helmsperson who can steer, handle charts, and keep a constant eye on the depthsounder. At night, even with a good helmsperson, you will be hard pressed staying clear of the many tugs and barges that tear through the canals and creeks full tilt 24 hours a day.
Communication with the commercial traffic is critical, both day and night. It is best to have two VHF radios, one tuned to Channel 16, the other to 13, the channel monitored by bridge tenders and tug drivers, and it is important to use your radio frequently. In many places there are blind turns where an oncoming tow and barge traveling at speed can take you by surprise. At bridges, even a mild turn can create a blind spot, and there may well be room for only one vessel to transit a bridge at a time. You should therefore establish radio contact with all bridge tenders well in advance of your arrival at a bridge. Plus, always be quick to contact commercial vessels to negotiate the details of any potentially tricky pass. Look at your chart, think ahead, and broadcast a securite on both 13 and 16 any time you approach constricted turns where visibility is obstructed or limited.
Traveling flat out, but stopping at night, a vessel that can cruise at better than 7 knots can normally make the trip from Norfolk to Beaufort in two days. Slower vessels will need to allow at least three. But these will be long, tiring days, mostly under power, and you'll be squandering a perfect opportunity to get in some high-quality slow-motion gunkholing and exploring. For this is definitely one of the most cruiseable sections of the ICW. There is lots of varied scenery, quiet anchorages, interesting towns and villages, and friendly locals to get to know along the way. There are also many places where you can wander quite a ways from the ICW itself, exploring tranquil rivers, creeks, and sounds all on your own.
Two more quick tips: Be sensitive to government security issues when transiting the Norfolk area, as it normally contains a huge conglomeration of military vessels. Security areas around military facilities and other potential terrorist targets are normally marked out with yellow buoys and should not be entered under any circumstances.
Also, when approaching the Beaufort-Morehead City area from the north on the ICW, do not take the shortcut channel that branches left directly to Beaufort at the Newport Marshes, no matter how tempting it seems. The chart shows 12 feet in this channel, but the surrounding shoals are shifty, and even vessels drawing 5 feet or less often run hard aground in here. It is better to follow the main channel down toward Morehead City, then circle round Radio Island and approach Beaufort from the ocean side.
Plan B: Creep Past Hatteras Inshore
Southbound vessels with masts over 65 feet can’t take advantage of the ICW and must confront Hatteras more directly. This means either plotting a course well offshore of Hatteras, or as close inshore as possible so as to stay just west of the relentless northeastbound current of the Gulf Stream.
The inshore route should not be undertaken lightly, but in settled conditions it is safe. To be sure of getting settled conditions, it is best to plan on putting into Norfolk to wait on weather. This will involve making a significant detour of as much 60 miles to the west if you are coming down directly from points east of Montauk, Long Island. You may well be saved the detour if the forecast is favorable as you approach the Hatteras area, but if you plan on stopping at Norfolk you won’t be forced to chance a rounding of Hatteras in rough conditions just to keep to your schedule.
There are no harbors or inlets anywhere between Norfolk and the cape. Ocracoke and Hatteras inlets, directly south of the cape, are both dicey shoal-draft affairs used mostly by sportfishing skiffs in calm conditions and are not viable for sailing vessels of any size. The distance between Norfolk and Beaufort, the next safe harbor south of the cape, is just about 200 miles by way of Diamond Shoals, so a safe weather window of at least 36 hours should be sufficient for most large sailboats taking this route.
Approaching Diamond Shoals you should keep a close eye on your speed over the ground, and when it starts to drop keep shifting course to the west to stay out of the main body of the Gulf Stream current. Sometimes the western edge of the Stream will be several miles east of the lighthouse (a 175-foot Texas-style platform tower that has been standing since 1967) that marks the outer edge of the shoals, and you’ll have plenty of room to turn the corner. Other times the current may be flowing right over the edge of the shoals, and you’ll be forced to pass over the shoals inside the light to stay clear of it. As soon as you are past the shoals, however, the gap between the shore the Stream will quickly grow wider as you head south into the great bight of the Carolina and Georgia coast.
Some aggressive skippers I have sailed with are willing to chance the inshore route around Hatteras in less than settled conditions. Normally when a cold front passes through, the strong northwest winds behind it will blow at a right angle across the Stream without directly opposing it. A wicked cross-sea will kick up, and though it can be very uncomfortable, it is not untenable. In such conditions, however, you should definitely stay east of the Diamond Shoals light, even if this means bucking the Stream for a while. If the wind is more in the northeast, or if there is any chance of a low forming in the area, or if, in a worst-case scenario, there is a hurricane headed in your direction, you want to be very sure you are safely at Norfolk waiting for things to improve.
Plan C: An End Run Offshore
An offshore route around Hatteras will immediately recommend itself to any careful skipper who enjoys ocean sailing. It makes good sense in particular if you are starting from New York City or farther north and are heading down as far as southern Florida or the Bahamas. And if you are heading east of the Bahamas, it will of course be by far the most efficient route, unless you are intent on following the Thorny Path and bucking the tradewinds sailing from island to island down the Antilles.
The strategy behind this route is simple: get yourself east of the Gulf Stream well north of Hatteras, then make your southing out in the open ocean, hundreds of miles from shore. Out here--far from shoal water, lee shores, and the Gulf Stream--is where any experienced sailor would much rather be if the weather suddenly turns to crap.
From the vicinity of Cape Cod as far down as Hatteras, prevailing winds are generally southwest, allowing for a nice reach across the Stream. The passage of a cold front will bring strong north to northwest winds that can help you make good time heading south. Off the mid-Atlantic portion of the coast, winds will be more variable, and the effects of passing cold fronts will still be quite pronounced. As you head further south, cold fronts become less of a factor, and you are more likely to pick up southeast or easterly breezes that will help you close the continent again.
Electing this option, however, does mean you need to prepare your crew and boat for a full-on ocean passage of six days or more. It will also probably be impossible to pick out a weather window big enough to get you all the way south in one hop without getting your feathers ruffled. You should be able to pick out a window that will see you safely out to and over the Stream in calm conditions, and, of course, you should keep your eyes peeled for any evidence of a hurricane or tropical storm forming anywhere near where you want to go. But the cold fronts sweeping off the continent come at regular enough intervals this time of year that you can pretty much count on catching a piece of something once you are offshore.
If your boat is sound and you are willing, you will find that any such experience will be far more tolerable and much less nerve-wracking the farther you are from Hatteras.