Damage was reported on at least two of the three legs of the peninsula, popular with tourists, especially from Russia, southern Europe and the Balkans.
Huge trees with their roots in the air, other trees split down the middle, could be seen around hotels in Nikiti, on the second leg.
Prime Minister Kyriakos Mitsotakis, whose government was sworn in this week after winning elections on July 7, cancelled his morning schedule and was being continuously briefed on the situation, a government official said.
Greek government spokesman, Stelios Petsas, said two Russian, two Romanian, and two Czech nationals had lost their lives, including two children. A seventh body was later discovered.
Such severe weather is unusual in Greece, where summers are typically hot and dry. One meteorologist described conditions as “extremely unusual” for this time of year.
(Production: John Ludlam, Idyli Tsakiri, Deborah Kyvrikosaios, Helena Williams)