We stayed three days in Treasure Cay Marina, Great Abaco and Friday, the 1st moved ten miles NE to Green Turtle Cay as part of our plan to get ready for our transit back to the US. Green Turtle Cay is one of a long string of "out islands", five to ten miles off the eastern shore of Great Abaco, the northern most Bahama Island. Just south of Green Turtle Cay and north of Great Guana Cay is an inlet called Whale Channel Cut that is one path to the deep ocean (one to two miles deep!). This is the path we had been planning to take to begin a 400 nautical mile sail to Charleston, SC.
The trip is expected to take three days (68 hours to be exact) if we cover 140 miles a day, a little under six knots, on average. We often sail faster, as fast as 8-9 knots. But, 140 miles a day is a conservative number and a starting point in our planning. Choppy seas will slow the boat down and waves coming at you do the same. So, we try to avoid these. But, it's not always possible. So, we try to factor in a variety of conditions, while gathering weather data from public sources and a couple of sailing weather professionals to come up with as clear a picture as possible for the following 3-4 days. Technology is wonderful. Weather forecasting has certainly benefited from this.
The first picture below shows our two possible routes we've been considering.
The green line shows our eastern route option. This was our intention, but weather and other considerations influenced choosing the west route. The green line/east route would be a 3.5 day sail. We would not benefit from a Gulf Stream "push". But, it looks like the wind and waves would make this a good choice.
The west route is shown as a red line on the left and takes us first to Great Sale Cay, about 60 nautical miles west of our current location. At that point it turns north. The reasons for considering this is that it allows us (if we wish) to anchor one night at Great Sale Cay and reduce the number of continuous days at sea, plus another two days of pleasant sailing on "the bank" where the islands protect against swells and is much more gentle than open ocean. It also takes better advantage of the push from a north flowing Gulf Stream than the eastern route, thereby giving us a quicker ride.
We (with help from the pros and sailing friends) try to match our route (first picture below) with the stream, wherever possible, if and when the wind/waves are also from the south, which is what we've been waiting for. You can see in the pictures that the stream is closer to Florida. The red route rides the stream north for a longer time, giving us a two to three knot boost for quite awhile.
Picture of our possible routes.
We're taking the west one - click to enlarge.
We'll take the red line!
Gulf Stream Sunday midnight
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We'll try to incorporate the green, yellow and red stream into our plan.
Wave height and Direction Sunday
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The waves are from the east, but during the folloing few days clock to the south, so we'd have following seas (almost) way better than from the north.
Wind Direction and strength Sunday
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Wind is behind us and agrees with the motion of the stream. This is the single most critical issue. If wind is from the north (opposing the direction of the stream) wave height and wave period (how close together and how "sharp" they are) makes for a very bad and slow ride.
If you're interested to see more ocean weather go to www.passageweather.com. It's an excellent site.
There are several other sailboats planning their return to the states. Everyone has their weather sources and ways of interpreting them. Most use a professional weather router. Chris Parker is the most widely used here. Jennifer Clark is another well-known router who specializes in Gulf Stream crossings, often for high end races. We decided to use Commander's Weather, based in Nashua, New Hampshire, of all places. We've been wanting to use them for years (now's our chance!) We called them last week because there had been talk of two very significant weather systems that could cause real issues.
There was a large low pressure area that went near the Carolinas last weekend with winds over 40 knots.
Then a sub-tropical LO began to form north of the Bahamas, travelled up the coast of the US and became the storm "Ana". So we are happy we waited a week to see how this has developed.
A fellow cruiser sends us Chris Parker's daily email which details the conditions in the Caribbean, the Bahamas, and the eastern seaboard. This, along with Passage Weather and Commander's gives us a good picture to match up and study all together.
Commander's will provide detailed information before our departure and during our trip. They confirmed that Ana will be gone before we arrive in Charleston on Wednesday morning. We'll use our satellite phone to call them once a day.
So - our wait has been rewarded. We are on our way west with our new friends Eric and Pat on "Cutter Loose" an Island Packet 460. We will meet them tonight at Great Sale Cay. Then, we have two options. Hang at Great Sale on Sunday and leave from there around 6pm. Or, sail early Sunday to Mantanilla Shoal and anchor on the bank for a rest and leave at 1am Monday morning. Either way, we calculate a morning arrival into Charleston. And, it will be nice to have another boat out there to occasionally check in with during the wee hours of morning.
We expect to have winds out of the South at less than 15 knots. There will be a fair amount of motor-sailing, but this is preferred over bashing into waves and dealing with high winds.
We sent a "Float Plan" to Sharon's sister Pam and Greg's sister Pam. You can all track us on SPOT to see how we are progressing.
We also log a "Float Plan" on the "Small Vessel Reporting System" of the Customs and Border Patrol which we hope will allow us to "clear-in" by phone, instead of having to traipse over to the office.
We will "talk" to you once we hit Charleston and get some rest. 'Til then....
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