An EF3 tornado occurred in southeastern Italy causing one casualty and estimated damage of 60 MEUR on 28 November 2012. At approximately 1050 Local Time, this tornado, which initially formed as a waterspout, moved inland. The environment where the tornadic supercell developed was characterized by large vertical wind shear in the lowest 1 km of the atmosphere and moderate conditional instability. The WRF-model numerical simulations show that it is possible to produce the track, change in intensity, and evolution of a simulated supercell thunderstorm similar to the actual one that spawned the tornado in Taranto, southern Italy. The genesis of the simulated supercell is due to a combination of mesoscale-meteorological features: warm low-level air advected toward the Ionian Sea, combined with a mid-level cooling due to an approaching trough, increased the potential instability; the intense vertical shear favored the possibility of supercell development. An unusual feature of the present case of tornadogenesis is the central role of the orography, which was verified in a sensitivity experiment where the orography of Calabria was reduced by 80%.
Numerical simulation of a tornado supercell in the Mediterranean
2017
Abstract
An EF3 tornado occurred in southeastern Italy causing one casualty and estimated damage of 60 MEUR on 28 November 2012. At approximately 1050 Local Time, this tornado, which initially formed as a waterspout, moved inland. The environment where the tornadic supercell developed was characterized by large vertical wind shear in the lowest 1 km of the atmosphere and moderate conditional instability. The WRF-model numerical simulations show that it is possible to produce the track, change in intensity, and evolution of a simulated supercell thunderstorm similar to the actual one that spawned the tornado in Taranto, southern Italy. The genesis of the simulated supercell is due to a combination of mesoscale-meteorological features: warm low-level air advected toward the Ionian Sea, combined with a mid-level cooling due to an approaching trough, increased the potential instability; the intense vertical shear favored the possibility of supercell development. An unusual feature of the present case of tornadogenesis is the central role of the orography, which was verified in a sensitivity experiment where the orography of Calabria was reduced by 80%.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


