Rainfall has a Mediterranean distribution all over the island, with almost totally rainless summers and wet autumns, winters and springs. However, in summer, the rare rainfalls can be characterized by short but severe thunderstorms, which can cause flash floods. The climate is also heavily influenced by the vicinity of the Gulf of Genoa (barometric low) and the relative proximity of the Atlantic Ocean. Low pressures in autumn can generate the formation of the so-called "Medicanes", extratropical cyclones which affect the Mediterranean basin. In 2013, the island was hit by several cyclones, included the Cyclone Cleopatra, which dumped of rainfall within an hour and a half. Sardinia being relatively large and hilly, weather is not uniform; in particular the East is drier, but paradoxically it suffers the worst rainstorms: in autumn 2009, it rained more than in a single day in Siniscola, and 19 November 2013, locations in Sardinia were reported to have received more than within two hours. The western coast has a higher distribution of rainfalls even for modest elevations (for instance Iglesias, elevation , average annual precipitation ). The driest part of the island is the coast of Cagliari gulf, with less than per year, the minimum is at Capo Carbonara at the extreme south-east of the island , and the wettest is the top of the Gennargentu mountain with almost per year. The average for the entire island is about per year, which is more than enough for the needs of the population and vegetation. The Mistral from the northwest is the dominant wind on and off throughout the year, though it is most prevalent in winter and spring. It can blow quite strongly, but it is usually dry and cool.