A severe storm with the characteristics of a hurricane has reached western Greece.
The islands of Zakynthos and Kefalonia as well as Ithaca were initially affected.
The ferry connections with the mainland have been discontinued.
Greek meteorologists named the storm "Ianos".
Meteorologist Christina Souzi spoke on the news channel "Skai" of a so-called Medicane, a Mediterranean hurricane.
This is a storm low that can form in the Mediterranean region towards the end of summer, when the water there is still high.
As soon as it reaches the mainland it becomes less violent.
A medicane is accompanied by strong winds and rainfall.
Most recently, the Medicane "Sorbas" caused considerable damage in Greece in 2018.
"It was a rare phenomenon in the Mediterranean. Now with climate change it will probably happen more often," said the head of the Greek Meteorological Office on state television, Kostas Lagouvardos.
According to the authorities, winds on Zakynthos reached strength ten to eleven on Thursday afternoon.
"Do not go on the streets. Secure everything that can fly around. Go to higher floors if there are floods," said the chief of civil protection, Nikos Chardalias, after a crisis meeting in Athens on state television.
The weather service of the Swiss meteorologist Jörg Kachelmann wrote on Twitter that there could be an "exceptionally strong storm".
Schools stay closed
The weather department called on sailors to go to the nearest port as soon as possible.
The schools in eight regions affected by the storm should remain closed on Friday, ordered the community service.
In addition to the islands in the Ionian Sea, which are likely to be hardest hit, the Peloponnese peninsula, central Greece and, in some cases, the island of Crete will also feel the effects of the storm.
Athens could also be affected by heavy rains and stormy winds.
"But we cannot say exactly how the Medicane will move," said meteorologist Lagouvardos on state television.
Icon: The mirror
fek / dpa