Bora

Bora is a catabatic wind, ie falling and adiabatic compression, originating from north / northeast, which blows with particular intensity especially towards the High and Middle Adriatic and towards some areas of the Aegean and the Black Sea in the presence of strong Barricade gradients between continent and sea.

The snow does not go in one direction, according to the law of Buys Ballot, but fluctuates around an average direction that is typical for each location. Its characteristic is to be a "discontinuous" wind, or to show up with stronger gusts, interspersed with less intense gusts. Such gusts are commonly called "refoli". Blows especially in winter, and is called "dark snow" with covered sky or rain or snow.

On the Gulf of Trieste, like the whole of the Adriatic, Chioggia, the Venetian lagoon, Romagna and the coasts of the northern Marche, up to Monte Conero, the typical direction is that of E-NE. In the Venice Giulia, the wind, due to the great differences in temperature between the Carso plateau and the colder, and the much warmer coast, is greatly enhanced, becoming furious and turbulent, with gusts that can overcome The threshold of 150-160 km / h.

The relatively dense, dry continental Arctic air descends to the Mediterranean from several gates ("gates") on the Adriatic: the Triveneto in particular flows through the "Postumia Gate" considered the "Bora Gate" as antonomasia - a depression of the Alpine chain in the Julian Alps, between the Karst plateau of Mount Nanos, also known as Monte Re (Nanos-Hrušica) and the Nevosi Mountain (Snežnik-Javornik) group - it particularly invests in the Triestian sector, To mitigate a narrow band northwest from the Monfalcone and to the southeast from the northern part of White Istria.