Sleeping well at anchor: an overnight checklist
A night at anchor is mostly decided in the hour after you arrive. What we check before dark, so that if something does wake us, we already know what to do.
In this piece
- The overnight anchorage checklist
- Read the forecast for the night, not the afternoon
- Swing room for a 180 degree shift
- Show an anchor light
- Snubber on, chafe guarded
- Lift the dinghy
- Stop the things that bang
- Rolling at anchor when the swell gets in
- Ready to move in the dark
- Set the alarm and decide who wakes for what
Anchoring overnight goes well on the nights you prepared for in daylight. Read the forecast through to the morning, leave room to swing a full 180 degrees, show an anchor light, rig the snubber and get the dinghy out of the water. Then go below with a torch by the companionway, the engine ready, a way out you could find in the dark, an anchor alarm set, and an agreement about who gets up for what.
None of it takes long. The checklist comes first. After it come the items that turn out to be less simple than they look.
The overnight anchorage checklist
- Forecast read hour by hour to the morning: direction and gusts at midnight, at 3 am and at dawn.
- Room to swing a full circle on the chain you have out, clear of rocks, shallows and other boats.
- Scope set for the strongest gust of the night.
- Anchor backed down on, and a transit noted from the cockpit.
- Snubber rigged, with chafe protection where it touches the boat.
- Anchor light on.
- Dinghy lifted, or on a short painter with the outboard off it.
- Halyards tied off away from the mast, nothing loose on deck.
- Head torch, shoes and a life jacket by the companionway.
- Engine key where everyone knows, and no lines in the water.
- The track you came in on saved, and a plan for leaving in the dark.
- Phone on charge and an anchor alarm set, loud enough to wake you.
- Who gets up for what, agreed before anyone is asleep.
Read the forecast for the night, not the afternoon
Most anchorages are picked for the wind that is blowing when you arrive. Most bad nights come from the wind that turns up after dark. So read the hourly forecast right through to the morning, and look at the direction as hard as the strength.
On warm coasts the pattern repeats itself. The afternoon sea breeze dies around sunset and the bay goes quiet. Some hours later the land, which cools faster than the sea, sends a land breeze down toward the water from roughly the opposite direction. Under high ground the cold air can drain down the slopes hard, a katabatic wind, gusty enough to have you checking the anchor at 3 am in a bay that was flat at dinner. The Aegean adds the meltemi, which often eases in the evening and builds again the next day, but not every night; in a strong spell it blows straight through. Our guide to the meltemi goes into its habits.
Look at the gusts as well as the mean wind, because at anchor it is the gusts that load the chain. In late summer, look for thunderstorms too. A squall can bring 40 knots from a direction nobody forecast, and it is the classic way for a well-set anchor in a good bay to end up dragging. If storms are possible, let out more chain, leave more room and sleep lighter.
Swing room for a 180 degree shift
When the land breeze replaces the sea breeze, the boat swings round to the far side of her anchor and ends up as far beyond it as she lay behind it at dinner. Whatever was well beyond your bow can now be close under your stern: the beach, the rocks off the point, the shallow patch you anchored just short of.
So look at the whole circle, including the half you are not lying in. Take the chain out, add the boat’s length, and check that the circle clears the shore, the shallows at the lowest water of the night, and the boats around you wherever their own swing will put them. If the circle only works for the wind you have now, move now, in daylight, rather than at 2 am. The same sum sets the anchor alarm, and setting an anchor alarm radius works through it with numbers.
Show an anchor light
The rule is Rule 30 of the COLREGs, the international collision regulations. A vessel at anchor under 50 m long shows an all-round white light where it can best be seen. The only exemption is for boats under 7 m anchored away from channels, fairways, anchorages and anywhere other boats normally go, which describes very few places a cruising yacht spends the night. Just show it, from sunset to sunrise. (By day the same rule asks for a black ball forward. Few yachts bother. It is still the rule.)
“Where it can best be seen” deserves some thought. A masthead light carries a long way, but to someone in a dinghy coming back across the bay after dinner it is one more star, far above their line of sight. Many cruisers add a second, low light in the cockpit or hanging from the boom. That is the one a dinghy or a small motorboat actually sees, and it helps you find your own boat among twenty others. An LED anchor light draws so little current that there is no excuse to leave it off.
Snubber on, chafe guarded
Rig the snubber even in a flat calm. It takes the load off the windlass, softens the jerk when the boat sails up to the end of her chain and falls back, and stops the chain grinding on the bow roller, which on most boats is the noise you hear in the forward cabin all night. Put chafe protection wherever the snubber bears on a fairlead or the toe rail. One that saws through at 4 am leaves the chain snatching at the windlass, and you will hear about it.
Chain dragging over rock as the boat swings makes its own noise, a dull grinding that comes up through the hull. On its own it means nothing worse than a noisy night. If it comes with the boat lying beam on, or with a transit that has opened, go and look harder; the signs your anchor is dragging are worth knowing by heart.
Lift the dinghy
A dinghy left on its painter overnight nudges the hull in a calm and sails about in a breeze. In a squall a light inflatable can flip, outboard and all. And when the wind drops and the boat drifts back over it, the painter is perfectly placed to wrap round the propeller at the moment you need the engine.
Lift it if you can: on davits, onto the foredeck, or hoisted alongside on a spare halyard, with the outboard on its bracket on the pushpit. If it has to stay in the water, take the outboard off, shorten the painter so the dinghy cannot get under the stern, and lock it to the boat. In a lot of cruising grounds the dinghy is the thing that goes missing at night. A lifted one rarely does.
Stop the things that bang
Halyards slapping the mast are the classic, and the cure is free: pull them away from the mast with a sail tie or a length of shock cord to a shroud, or take them out to the toe rail. The neighbours will thank you. Then go round the rest of the boat. Sheet the boom in hard or tie it off. Bring in fenders left over the side, take up the slack in the topping lift, lash the swim ladder, and listen for the burgee halyard and any shackle that can tap against something. Below, wedge whatever rolls in the lockers; a tin rolling about at 2 am sounds like something breaking.
Some noises come from the water. Wavelets slapping under a reverse transom or the bridge deck of a catamaran can be maddening, and the only real fixes are changing the boat’s angle to them or moving.
Rolling at anchor when the swell gets in
The nights that wear people out tend to be the rolly ones: the wind holds the bow one way and a swell from somewhere else rolls in on the beam. The swell may come from a blow far away, or it may wrap round a headland into a bay that looks sheltered on the chart.
A bridle can turn the bow toward the swell. Make a line fast to the chain with a rolling hitch or a chain hook, lead it aft to a winch on the quarter, and let out a few more metres of chain so the line takes the load. The boat now lies at an angle to the wind, and by winding the line in or easing it you can bring her round to meet the swell closer to head on. It only works while wind and swell stay where they are, so check it in the night.
A flopper stopper is a plate or a folding frame hung in the water from the end of the boom, with the boom guyed out to the side. It sinks freely and resists being pulled up, so it damps the roll. They look improbable and work better than you would expect.
A stern anchor holds the boat’s head into the swell, but it also stops her swinging to a wind shift, so the night’s land breeze catches her on the beam. Use one only where the forecast is steady and the boats around you are doing the same, or in a spot too narrow to swing in anyway. When none of that helps, the real answer is a different bay, chosen in daylight. Our guide to choosing an anchorage covers how swell gets into places you would not expect.
Ready to move in the dark
Set the boat up so that if the alarm goes at 3 am in the rain, you can be on deck and under way in a couple of minutes.
A head torch with a red setting, shoes and a life jacket wait by the companionway. The engine key is in the ignition or somewhere everyone knows. Nothing is in the water to foul the propeller: no dinghy painter, no fishing line, no swim ladder lanyard. If the windlass has a breaker or an isolator, everyone aboard knows where it is.
Then the way out. Keep the track you came in on, on the plotter or the phone; in the dark it is the only path you know is clear. Before dinner, look at the entrance, note what lies near it, and decide where you would go if you had to leave the bay altogether: the next anchorage, or open water to sit out the rest of the night. Deciding that over dinner takes five minutes. At 3 am, with the boat dragging, it takes longer than you have.
Set the alarm and decide who wakes for what
The phone goes on charge somewhere its alarm will wake you through a closed cabin door, and the anchor alarm goes on with a radius worked out properly and the centre on the anchor. A phone running GPS all night with the screen awake uses more battery than people expect, so plug it in.
Then agree who does what before anyone is asleep. On a two-person boat it can be as simple as this: whoever is nearer the companionway goes up first and looks, and the other starts the engine if called. With a bigger crew, say who goes forward and who takes the helm. And agree what is worth waking for. Our rule is that anyone woken by a change in the wind, the motion or the noise goes up and looks, and wakes the skipper if two signs say something is wrong. Nobody gets grief for a false alarm at anchor.