| This is the first modeling reconstruction of the whole aspects (both meteorological and
oceanographic) of the storm which hit Italy on
4 November 1966, producing 118
victims and widespread damages in Tuscany, at the northern Adriatic coast and
in the
north-eastern Italian Alps.
The storm was produced by a cyclone
which formed in the western Mediterranean and moved eastward towards Italy,
reaching the Thyrrenian Sea, and then northward.
The most peculiar characteristic of the storm has been the strong zonal
pressure gradient
and the consequent intensity and long fetch of the south-easterly
sirocco wind, which advected
a large amount of warm moist
air, and determined exceptional orographic precipitation over Tuscany and the
north-eastern Alps. The funneling of the wind between the mountain
chains surrounding the Adriatic basin further increased the wind speed and determined
the highest ever recorded storm surge along the Venetian coast.
This study shows that
present models would be able to produce a reasonably accurate
simulation of the meteorological event
(surface pressure, wind and
precipitation fields, and
storm surge level).
The exceptional intensity of
the event is not suggested by single parameters such as the sea level pressure minimum, the wind speed
or the total accumulated precipitation.
In fact, the precipitation was extreme only in some locations and
the pressure minimum was not particularly deep.
Moreover, the prediction of the damages produced by the
river run-off and landslides
would have required other informations concerning soil condition, snow coverage,
and storage of water reservoirs before the event.
This indicates that an integrated approach is required for assessing the probability of such damages both on a weather forecast and on
a climate change perspective. |