| Sirocco: This term is an
all-inclusive name given to warm (or hot) southeast to
southwest winds originating in the hot, dry air masses
over Libya and Egypt, flowing northward into the
south-central Mediterranean basin. Siroccos
occur as a result of surface and upper level depressions
moving eastward across the southern Mediterranean Sea or
north Africa. The air flows northward from the Sahara
desert, south of Tunisia, as well as from Libya and
Egypt, producing hot, dry and dusty conditions over the
northern African coast, resulting in poor visibility and
damage to instruments and equipment. As it travels
northward, the Sirocco builds moisture and
clouds, causing fog and rain within the northern
Mediterranean regions such as Italy and Greece. The onset
of a gale-force Sirocco often occurs as a
surface low moves into the Gulf of Gabes from Tunisia,
combined with the passage of a deep 500 mb trough
extending well into north Africa and positioned west of
the Gulf of Gabes. The gale-force Sirocco is
most common during the spring.
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