Bene505, can you elaborate a little more on your anchoring details. How big, how long, chain/rode, how deep, what directions, aft/stern/midship?. So, If you where in Long Island, did you get mostly east, south, wind or what. I read you had 400' of rode, was that on one anchor? Others the same? What type of anchors? Splicing, etc...
Firstly, I like having the boat where the storm isn't. Because I'm already in a good spot -- great holding, not too deep so there a great scope ratio -- this sometimes means taking action a little later, after seeing where the hurricane's track is going.
I search eBay routinely for things that I'd like to add to the boat. So when 2 new FX-125s came up, I bought them (and combined shipping!). Same for a high strength Danforth 90H. I use all-chain for one anchor always. I don't like to have to trust nylon line, but will do so if needed for more scope, after the 150' of chain is out, like when anchoring in 50 feet of water at Block Island. I have a Manson Supreme 60 on the chain now. (It's light enough that I can remove it when on a mooring, so the mooring bridals don't get chafed.)
I also like swinging in the breeze (not a Jordache Jeans reference), letting the boat swing to have the least wind resistance. That means all anchors off the bow. An anchor at the stern seems like it adds too much windage when the wind shifts.
I also apply wrapped cotton towels to the lines, secured in place at the ends and midpoint (of the towel) with wraps of lighter line. There's a good picture of it from last year's hurricane Irene.
This prep was also for a hurricane that only came within about 100 miles.
In my humble opinion, it's the chafe that gets you, as well as the lines getting caught up over the top of the roller when the boat weaves and dodges. But there as people on the forum that are much more expert about this than me; all one can do is try to learn from them.
For this storm, it was: 1) 140 ' of chain on a Manson Supreme 60 to the south east, with plenty of snubber line, 2) 200 feet of heavy line (seen in the foredeck picture) to the east on a FX-125, and 3) 30' chain and 100 feet of line to the south. The anchors were in 10, 7, and 10 feet of water due to the storm surge.
I had to quickly get the shallowest anchor out after the storm passed over, or I'd be calling a friend with a catamaran to get it out. (Dave, in the picture above, built a 32' cat over the winter.)
As it turns out, the stout line seen on the foredeck floats!!! That added to my worries, since I didn't want to cause damage to other boats. But there was no boat traffic at all in this tight little dead end, on a weekday, during a hurricane. After the initial wind shift, the boat sat near it, and then right on top of it for the remainder of the storm. What do you do with about 400 to 500 feet of 7/8 or 1 inch floating line? I believe it's nylon on the outside and poly on the inside. Maybe use it for a sea anchor line? (It's awfully heavy to be carrying for that one purpose.) I hate cutting it up to make dock lines, so I'll probably sell it. Maybe get a school to do a tub-of-war?
The thing to remember when using multiple anchors, is that each individual anchor has to be able to individually hold the boat on it's own without the help from the other anchors, without any other anchor helping, like on it's own, as if the others weren't even there -- individually. (Hope that got the point across!) This type of mooring set-up costs a lot more that the traditional mushroom setup, but it's holding power is phenomenal and it's movable, like for when an hurricane comes nearby. Using these same anchors, I could have holed up in a lot of different places and felt very secure about their ability to hold.
It's mentioned in Chapman's that during the hurricane that went over the NY Yacht Club (1937 maybe?), the only 3 boats left anchored had this same system. All the other boats were on the shore. Of course if this was a real mooring, I'd have the anchors 120 degree apart. But the hurricane had very specific wind directions forecast. Each anchor mentioned above took it's turn holding the boat as the wind clocked around as forecast.
Oh, and I had more long line and another FX-125 on the deck as a reserve. If you have to cut away because a big boat is bearing down on you in the storm, you'll need something for after you maneuver out of the way.
I may have mentioned that I didn't plan on spending the night on the boat (my ride to shore flipped), but was glad I did. The wind was actually ripping droplets off the top of the water, but the small cove had waves of only 6 inches where I was. I'm not sure I could say it was a hurricane where I was. (And that's the point of being somewhere else.) But it was really windy for long time with some stronger gusts. The anchors did their job in a very protected cove.