Etesians

Strong, dry north to north-easterly katabatic winds that blow seasonally over the Aegean Sea during the summer months.

The Etesians, also known as Meltemi winds in Greek, are a prominent meteorological phenomenon affecting the eastern Mediterranean, particularly the Aegean Sea. These winds typically occur from late May through to September, peaking in July and August. They are driven by a pressure gradient between the high-pressure systems over the Balkans and the low-pressure systems over the eastern Mediterranean and Asia Minor. The result is a consistent flow of air from the north or north-east, with wind speeds often reaching Force 5 to 7 on the Beaufort scale, and occasionally stronger.

The Etesians are generally dry and bring clear skies, offering relief from the intense summer heat. However, their strength and persistence can significantly impact navigation and sailing conditions. Mariners must be cautious, especially in the central and southern Aegean, where the wind can funnel through island channels and accelerate. These winds can arise suddenly and may last for several days, making anchoring and passage planning critical for safety. While beneficial for cooling coastal areas, the Etesians can also create choppy seas and strong surface currents, which require careful handling by skippers and crew.