Every conversation about a summer charter in Greece arrives at the same word. The meltemi is a dry northerly wind that blows across the Aegean from roughly mid-June to mid-September, strongest in July and August, and it shapes where boats go, when they leave and whether the crew enjoys the crossing.
It is not a storm. It is a reliable, forecastable wind that sailors plan around every year. But it is strong enough that a crew who has not heard of it can have a bad week, and a crew who understands it can have a superb one.
What it is
The meltemi is driven by the pressure difference between a high over the Balkans and a low over Turkey in summer. Air pours south across the Aegean, funnelled and accelerated between the islands. It typically blows at force five to six, gusting seven, with stronger spells of a few days when it reaches force eight in the central Cyclades. It usually eases at night and in the early morning, and it can drop away entirely for days at a time before returning.
Because it is a fair-weather wind, the sky is clear and the sun is out while it blows. That is what makes it deceptive: it looks like a perfect day from the harbour.
Where it is strongest
The central and northern Cyclades take the full force: the channels around Mykonos, Tinos, Andros, Paros, Naxos and Ios are the windiest water in the Mediterranean in August. The Dodecanese, further east, get it too, with Kos and Rhodes on the edge. The eastern Sporades and the north Aegean are affected but less consistently.
The Ionian on the west coast is largely outside it, with its own gentle afternoon breeze instead. The Saronic Gulf gets a weakened version and is sheltered by the mainland. The southern Peloponnese and Crete’s south coast are also calmer.
How experienced crews sail it
- Go with it, not against it. A Cyclades route runs south with the wind behind and returns north in stages, choosing calm mornings for the beats. A route that fights north into the meltemi every day is exhausting.
- Leave early. The wind is lightest at dawn and builds through the morning. A 6 am departure covers most of a passage before it reaches full strength.
- Reef before leaving harbour. A boat that starts with a reef in and shakes it out is a boat that stays comfortable.
- Pick harbours for shelter from the north. Bays open to the north are untenable; the south coasts of the islands are where boats spend the night.
- Build in a wind day. When the forecast shows force seven for two days, the sensible plan is to stay put and explore the island. A week with one day in harbour is a normal week.
- Read the forecast daily. The meltemi is well forecast several days ahead. The mistake is not checking.
What it feels like aboard
With the wind behind, a modern yacht in a force six is fast, lively and, for most crews, exhilarating. Beating into it is wet, slow and tiring, with short steep seas between the islands. At anchor in a sheltered bay the wind whistles in the rigging but the water is flat. In a harbour open to it, boats surge on their lines and nobody sleeps.
For a crew with sailing experience it is the best wind of the year. For a family, a group of non-sailors or anyone prone to seasickness, it is the reason to choose another area in July and August, or to book a skipper who knows how to use it.
Timing a Cyclades charter
Late May and June see a gentler, intermittent meltemi and warm enough water. September, especially the second half, has the wind easing and the sea at its warmest. July and August are for crews who want the wind or are prepared to plan around it. October is calm but cooler.
The catamaran question
Catamarans are more comfortable at anchor in the meltemi and do not heel, but they do not sail upwind as well as a monohull and are affected by windage in harbour. Downwind and at anchor, they are the better family boat; beating north, a good monohull is faster and drier. Neither is a reason to skip the Cyclades in summer; both are a reason to plan the route.
Frequently Asked Questions
When does the meltemi blow?
Mid-June to mid-September, strongest in July and August, usually easing at night and dropping for a few days at a time.
How strong is the meltemi?
Typically force five to six, gusting seven, with spells of force eight in the central Cyclades channels.
Which Greek islands are least affected?
The Ionian islands, the Saronic Gulf and the southern Peloponnese, all sheltered by the mainland from the northerly.
Can beginners sail the Cyclades in August?
With a skipper and a route planned around the wind, yes. Bareboat beginners should choose the Ionian or the Saronic instead.