Anchoring for a Hurricane

Hurricanes are no regular storm, they almost take on a life and personality as they crawl through the skies. Avoiding these monsters should be the first choice, but if you are land locked and the storm is coming at you, you will need to prepare. 

Previously, we discussed the options of securing your yacht for the storm. They are: tying up in a marina, anchoring, or sailing through it. Marinas are preferred if you already have a slip and you know the yacht will be safe there. Sailing through it is a dumb idea and should be avoided. We will now delve deeper into how to anchor for the storm. 

The first thing you need to do is find a protected place to hide. Preferably one with land all around you to stop the waves from tugging on the anchor in the bottom.  

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The next thing you need to do is let out enough anchor rode. Chain is preferred, as it won't chafe on anything on the sea bed. The minimum scope for all chain is 5:1.  This means that for each foot of water depth, you will let out 5 feet of chain. 5:1 is fine for light weather, but this is a severe storm we are dealing with, so the scope needs to be increased.

The minimum scope for an event like this is 10:1. Naturally, this limits how deep you can do this in by how much chain you have. If you carry 300 feet of chain, then you can only do this in 30 feet of effective depth. This means that the height from the bow roller to the bottom is only 30 feet. If you have a 10 foot high bow roller from the waters surface, then you can only reach 10:1 scope in 20 feet of water! 

After you let out all of that chain, you then want to reduce the amount of shock load that the system will encounter. Chain is great for anchoring because it is heavy and the weight of the chain will form a nice catenary curve leading to the anchor. This means that the chain closest to the anchor will be horizontal and the pull on the anchor will be horizontal along the seabed. This reduces the risk of pulling the anchor up out of the substrate. 

Wind gusts will push your yacht back and waves will cause the bow to rise and fall. All of these movements will tighten the chain and snap on your ground tackle. To dampen these effects, we need to introduce some elasticity to the equation. 

You will want to use a very strong piece of 3-Strand nylon rope, as it will offer the most stretch available with the strength required. This line, called a snubber, will be tied to the chain itself and led to a cleat. More chain will be let out and the snubber will begin taking the load. I like to let even more chain out, causing it to drop straight down from the bow, letting me know that if the snubber stretches a lot, the chain will never come into tension. This will dampen any shock loads on the chain and anchor, leading to a much more secure anchoring. 

Now, to make sure the anchor is set well, you will want to drop it in a different from normal fashion. In cases like this, we will sail into the anchorage under full sail and drop the anchor while moving at speed and in the direction that the winds are predicted to be coming. 

If you are in the storm and sailing into the harbor of choice during the storm, then you already know which direction the winds are going to be blowing, and you can do this maneuver on a run. When the eye of Hurricane Jose was passing 20 miles East of us, we sailed into the anchorage on a run and under storm sails. The effective depth was 20 feet, so I only needed to drop 200 feet of chain for 10:1 scope. As we were sailing along, Maddie gave the signal that we were in the right place and I dropped our anchor with 100 feet of chain (5:1 scope). The anchor dug into the bottom as we moved over at around 4 knots and brought the yacht to an abrupt halt. The bow stopped and the stern swung around rapidly as it was still carrying all of that momentum. This let me know that the anchor was set and well buried, as it did not drag under those extreme conditions.

I then let out an additional 140 feet of chain, bringing our scope to 12:1. I let that sit for about an hour, making sure that the anchor was not going to drag. When we were certain of its holding, we then added the snubber to the equation. 

Should the anchor begin to drag, all we need to do is untie the snubber and let out more chain until it stops dragging. Then we can tie a second snubber (which is kept on the bow as well) to the chain to hold us, should we need it. 

Anchoring for a severe storm is a critical skill to have and should be practiced enough that you feel confident in carrying out the task when the moment arises.