I am far from an expert on this topic, but for sailboats; sea anchors and storm sails. The first is a parachute-like device that keeps the boat pointed in the right direction relative to the waves. The second is a small, tough sail used when any other sail, even while reefed, would be too big.
If you can't make it to shelter in time, it's better to weather the storm in open water than near the shore - at least that way, you won't risk hitting something and sinking.