At anchor in a Cycladic bay as the Meltemi builds
On 2 August the 15 m charter yacht Anemos lies at anchor in a bay on the north coast of a Cycladic island, 300 m off a lee shore, in 6 m of water with 40 m of chain and good holding. The morning forecast is north 5 to 6, occasionally 7 in the east, sea moderate. The synoptic chart shows 1016 hPa over the northern Balkans and 1005 hPa over south-east Turkey. At 14:00 the wind is 26 knots; by 22:00 it is a steady 30 knots with gusts well above that, and the yacht is pitching. The anchor alarm sounds once and resets. The nearest all-round shelter is 14 NM to the south, round a headland that must be passed at night. Three people are on board; one is seasick and vomiting. The chart shows a rocky patch 80 m to the east of the anchorage and a 30 m isobath 150 m offshore. The engine starts and runs normally, and the VHF is working.
1. Interpret the synoptic situation and forecast how the wind and sea state will behave over the next 24 hours at this anchorage.
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The 11 hPa difference between the Balkan ridge (1016) and the south-east Turkish low (1005) means tightly packed isobars across the Aegean: a classic Meltemi pattern – persistent northerly 6–7 Bft, strongest in summer.
Expected behaviour:
- Diurnal reinforcement. The thermal low over Anatolia deepens through the afternoon and the local sea breeze adds to the gradient wind, so the peak is usually mid-afternoon; the night and early morning are the relatively quieter phase – but 30 kn at 22:00 shows this is a strong event, not a breeze that will simply die at dusk.
- Duration. Such events run for two to four days. There is no reason to expect the morning to be materially better.
- Local acceleration. Gusts will be 30–50% above the mean where the flow funnels through valleys and accelerates off the hills; expect sudden veers of 20–30° and violent williwaws, not a steady breeze.
- Sea state. The fetch from the north is the whole Aegean, so 2–3 m is realistic offshore. The bay opens north, so it offers almost no protection; the 30 m isobath only 150 m offshore means the bottom shoals steeply and short, steep seas will break close in.
- Anchorage geometry. 40 m of chain on 6 m is roughly 6.7:1 – adequate scope, but the swinging circle is about 55 m, leaving very little margin to the rocky patch 80 m to the east.
2. Decide what to do tonight and set out the sequence of actions, including the alternative if you stay.
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Decision: leave now and go to the all-round shelter, while the engine is working and before the sea state makes weighing anchor dangerous.
Reasoning: the forecast trend is flat to worse for at least 24 hours; the bay is open to the north with a lee shore only 300 m astern; the anchor has already dragged or the chain has been snatched at least once (the alarm); there is only about 25 m of clearance to the rocky patch; and one of three crew is incapacitated, which halves the available hands for a night re-anchoring in 30 kn.
Sequence:
- Brief the crew, lifejackets on, secure everything loose, seasick crew strapped in and watched.
- Start and warm the engine, engine on load before weighing; prepare the anchor windlass and a second anchor ready to deploy.
- Motor slowly up towards the anchor, take the strain off, weigh and clear the chain; do not drive over the chain.
- Before departure, identify the headland lights, plot the track and fix a safe passing distance; keep the echo sounder on and stay outside the 30 m isobath but clear of the rocks.
- Slow passage round the headland; expect a wind shadow and then a hard gust as you come clear of it – the wind will shift and may come from a different direction on the south side.
- Anchor in the shelter with at least 5:1 scope, set the anchor under power in reverse, take transit bearings, set the anchor alarm and a 30-minute watch.
If staying instead: veer to 60–70 m of chain to add catenary, keep the engine running in gear at idle on standby, take bearings on two shore transits and log them hourly, and be ready to leave at first light.
3. What observations would confirm that the Meltemi is genuinely easing rather than just going through its daily cycle?
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Barometer. The decisive evidence is pressure: a rising trend at the low (or a falling trend at the ridge) means the gradient is relaxing. The barometer is the only instrument that tells you about the driving force rather than the local symptom.
Wind character, not just strength. A genuine easing shows as a lower mean with the gusts coming down proportionally, and the direction becoming steadier. A daily lull still carries sharp katabatic gusts off the hills – if the gusts are still 35 kn at dawn, the event is intact.
Trend over 24 hours, not one reading. Compare the same hour on consecutive days. A quiet dawn followed by a 30 kn afternoon is the diurnal cycle, not a change.
Official forecasts. Listen to the scheduled VHF/NAVTEX forecasts and gale warnings; a change in the wording from 'north 6 to 7' to 'north 4 to 5' across two consecutive bulletins is meaningful.
Sea state lags the wind. Even after a real easing, 2–3 m of swell will run for many hours. Do not move back to an exposed anchorage on the strength of a dropping anemometer, and do not assume an improved forecast means an improved sea at the entrance you have to cross.