A large convective system brought severe storms to Naples and the Balearics in early September.
09 March 2021
03 September 2015
Between 3–5 September several convective cells developed along a relatively weak airmass boundary. One of the most severe cells brought tennis ball-sized hail to parts of Naples. Figure 1 shows the supercell over the Italian city on 5 September.
by HansPeter Roesli (Switzerland) and Jochen Kerkmann and Sancha Lancaster (EUMETSAT)
The Meteosat-10 infrared imagery, animation from 3 Sept 00:00 UTC–5 Sept 10:00 UTC and Figure 1, shows the series of cells developing over the Mediterranean Sea. The severe storms were caused by a combination of instability (high moisture), lift (the trough can be clearly seen on the imagery) and wind shear (there was a jet over the area during the period).
Figure 2: Sandwich product, 4 September
On 4 September storms in Menorca, Mallorca and Malaga caused flash flooding and severe lightning — some planes had to make emergency diversions. Local papers in Menorca reported it was the worst storm for 33 years.
The YouTube video Inundacion en calas fons menorca es castell shows flood water sweeping through the streets.
The Suomi-NPP VIIRS infrared and visible sandwich product, 4 Sept 12:35 UTC, shows one of the intense cells over the Mediterranean Sea, to the east of Menorca.
The Meteosat-10 infrared imagery, animation from 5 Sept 00:00–10:00 UTC and Figure 1 (top right), shows the convection that brought massive, damaging hailstones to parts of Naples (Figure 3).
It was reported that several people and animals were injured, and vehicles and crops were badly damaged.
On Figure 1 a well-defined cold ring-shape cloud top can be seen, signifying a severe storm. The coldest cloud-top IR brightness temperature was -73.5º C at 09:00 UTC.
On the animated gif of the Meteosat-10 High Resolution Visible, 5 Sept 05:30–09:00 UTC (Figure 4), overshooting tops, ship-wave like plumes and gravity waves can be seen.
Supercell thunderstorm producing large hail in the Naples, Italy area (CIMSS Blog)
Three Jet2 planes declare emergencies as fierce storm rages over Ibiza, Majorca and Malaga (Mail Online)
Flash flood hits Menorca and egg-sized hailstones strike Aragon, Spain (sott.net)
Incredible Large Hail Stones (Grandine) hit Napoli, Italy | 05 09 2015 (YouTube/Nature Reporter)
Previous case studies
Spain hit by severe hailstorms twice in three days (1/2/3 July 2014)
Thunderstorm in Mallorca (29 Oct 2013)
Storms over Southern Italy (2 Sept 2010)
Super Typhoon Surigae
Super Typhoon Surigae was the strongest ever early season typhoon in the North Pacific.
Geldingadalir eruptions affect cloud microphysics
Altered cloud microphysical structure above Geldingadalir eruptions, April 2021.
Major eruption of La Soufrière volcano
Major eruption of the Caribbean volcano La Soufrière in early April 2021.
Tropical cyclone Seroja undergoes Fujiwhara effect
TC Seroja consumed an unnamed tropical storm in April 2021.
Major dust outbreaks - Africa, Middle East & China
Meteosat-8 spots series of dust outbreaks in March 2021.