My wife, Joyce, and I once anchored with several other sailboats off the northwest shore of Conception Island, an uninhabited island in the Bahamas, near a beautiful beach in 30 feet of clear water with excellent holding ground.
After a snorkel and a big meal, I turned on the radio and learned that a fast-moving cold front was due to hit that night. The northwest winds behind the front would turn our exposed anchorage into a dangerous lee shore, so we weighed anchor and headed for the east anchorage with the rest of the fleet.
We anchored as far north in the anchorage as possible. We were comfortable, but the boaters who anchored farther south spent the night rolling in the waves.
If we hadn’t known how to select an anchorage that would shield us from the effects of the cold front, we would have been caught on a lee shore in a strong blow and would have had to sail into the teeth of the gale or been blown ashore.
Avoid anchoring off a lee shore when wind and waves can push your boat toward shore. If you anchor in the lee—on the sheltered downwind side—with the wind blowing from the land, the wind will move your boat into deeper water if you drag anchor. Although your boat will generally be protected from wave action in the lee, be aware that waves bending around islands and headlands can cause your boat to roll uncomfortably.
Look for an anchorage with excellent holding ground and no underwater hazards to foul your anchor. The water should be deep enough to make the tidal range immaterial but shallow enough not to require excessive rode. Look for an area with little or no current and plenty of swinging room. –Samuel S. Sanford