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Mediterranean Hurricanes - Medicanes ?

Mediterranean tropical cyclones are an extremely rare weather phenomenon. These systems are a subject of some debate within meteorological circles whether they closely fit the definition of tropical cyclones, subtropical cyclones, or polar lows. Their origins are typically non-tropical, and develop over open waters under strong, initially cold-core cyclones, similar to subtropical cyclones in the Atlantic Basin. Sea surface temperatures in late-August and early-September are quite high over the basin (+24/+28°C), though research indicates water temperatures of 20 °C/68 °F are normally required for development. Cold air aloft appears to be the main trigger for instability in the development of these systems. If a "hurricane season" were ever to be demarcated in the Mediterranean, it would extend from August through January, based upon occurrences so far.
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Historical Events

Sardinia Devastated by Medicane Cleopatra

In yet another example of a Mediterranean Tropical Cyclone, on Monday 18th November 2013 the Island of Sardinia was devastated by hurricane force winds and torrential rain, floods and landslides. In 90 minutes a years worth of rain fell on the Island. See the article below for more information.

Italy Declares state of emergency in Sardinia after deadly cyclone

Reuters News Agency

NOAA Officially Designates Mediterranean Tropical Storm (01M) for the first time

Cyprus Mail  - 11th November 2011
(A sign of things to come ??)

ANYBODY who flew to the Cote d'Azur or Provence for some autumn sunshine this week might have been sorely
disappointed. An intense low pressure system developed in the western Mediterranean and  became  slow moving west of Corsica, dumping some intense rainfall and generating fierce winds.

This late in autumn the weather does  tend to turn in the Mediterranean, and only a couple of weeks ago (October 2011) Greece and Turkey were suffering heavy rain and gales.

This particular depression, though, was an odd one. As it developed, meteorologists watched satellite animations which showed it assuming the sort of shape associated with tropical cyclones, even suggestive of a central "eye". Before we get too carried away, the sea surface temperature in the Mediterranean  is not high enough to create or sustain a
hurricane. Near Corsica, the western Mediterranean has been at about 20C this week, and hurricanes
require water at close to 27C beneath them.
However, the storm exhibited sufficient tropical characteristics for NOAA in the US to grant it tropical storm   status through its  National Environmental Satellite, Data and Information Service (Nesdis). An advisory on Monday called it  01M (the M standing for Mediterranean), the first such ever issued for the Mediterranean.  Winds were above storm force with heavy thunderstorms breaking out, similar in intensity to those in the
tropics, and there was some coastal flooding. 

The department of Var, north of Toulon, recorded more than 400mm of rain in four days, and a gust  of 153kph hit
Porquerolles Island just offshore south of the city on Tuesday. Just east-south-east   of Toulon, 129mm of  rain fell on Ile du Levant on Tuesday alone, and there was a gust of 148kph.  The relatively high sea temperature was overlaid by cold air aloft, with temperatures of minus 20C at 5,000m-6,000m. That difference of 40 degrees meant a very unstable airmass, ideal for the formation  of such storms and for very deep convection to be sustained.

Similar Mediterranean storms are uncommon but not by any means unknown, and are given the rather playful
portmanteau name "Medicane" ? that is "Medi-terranean Hurri-cane". Two of the more recent  occurrences were in 1995 and 1996. In January 1995 there was a similar formation south-east of Sicily, and in October 1996 one over the
Tyrrhenian Sea, both of which had very distinct central "eyes". The 1995  storm could  arguably be called a proper  hurricane ? although strictly not because of the insufficient warmth of the sea ? because it had sustained winds, not gusts,
of around 145kph. These were measured by a German research vessel which ? fortunately or unfortunately
depending on your viewpoint ? got caught up in it. Highly appropriately the ship was called the "Meteor".

Other Possible Medicanes


Meteorological literature documents other Mediterranean Hurricanes occurred in September 1947, September 1969, September 1973, August 1976, January 1982, September 1983, December 1984, December 1985, October 1994, January 1995, October 1996, September 1997, December 2005, September 2006.

January 14-18, 1995

In the middle of January 1995, a cold front moved across the Mediterranean Sea. A
frontal wave developed along it on the 13th, and developed a low-level circulation the next day to the west of Greece. Convection built and organized around the center as it moved to the southwest, and by the 15th it resembled a tropical storm. It continued to
organize, and
developed an eye later that day. Though water temperatures were only 16 °C (61 °F), the storm was characterized by well-defined outflow, an eye, an upper level anticyclone, and a ship report of 136 km/h, 37.8 m/s (74 knots, 85 mph) winds, equivalent in strength to a
Category 1 hurricane. The system continued to the southwest and quickly weakened, making landfall on northern Libya as a convectionless vortex on the 17th. It dissipated the next day.

October 4-6, 1996

On October 4, 1996, a small vortex was first observed between Sicily and Tunisia. It
moved to the north-northeast, and quickly organized due to warm water temperatures. The system may have tried to develop a warm core, but only limited shallow convection was seen within its circulation. It passed over Sicily on the night of the 4th and crossed southern Italy
on the 5th. By the 6th, it entered the Adriatic Sea and dissipated.
The storm caused extremely intense precipitation and severe floods in Sicily and over the southern part of Calabria (480 mm over 2 days, with 285 mm on 4 October alone). It
produced gusts of up to 105 km/h, 29 m/s (55 knots, 65 mph), causing heavy damage in its short path.

October 6-10, 1996

As the previous system was at its peak, a frontal wave extended through the western
Mediterranean. It developed into a frontal low on the 6th, and strengthened and became better
organized as it moved eastward over warm waters. With little upper level shear, a warm core, an organized vertical structure, and a n eyewall, the system was possibly a
hurricane late on the 7th just before hitting Sardinia. Over land it lost its eye structure, but quickly reorganized and acquired an eye early on the 8th after crossing Sardinia. reached
hurricane strength the same day in the Tyrrenian sea. The storm retained its organization for a day before hitting northern Sicily on the 10th and weakening. Floods occurred on the Balearic Islands, Sardinia, and south Italy. On the 9th, serious damage from winds up to 145 km/h (78 knots) was reported over the Eolian Islands. Four people were reported dead.
The development of a hurricane in the central Mediterranean Sea was well-predicted by
computer models in the days prior to the storm's genesis.


March 27-28, 1999

A deep cyclone cutoff in the Gulf of Lyons on March 26. Winds at Portbou, Spain
increased to 150 km/h, 41.6 m/s (81 knots, 93 mph) by the evening of March 26. The
pressure of the cyclone fell to 998 hPa by midnight. By the morning of March 27, it was no longer connected to its occluded front and satellite imagery briefly revealed an eye feature, though convection around it was shallow. Water temperatures under the system were a mere 15°C (59°F) since temperatures at the 500 hPa level were quite cold; -28°C (-18°F). Soon
afterwards, the system weakened as it approached northern Italy.

See also

South Atlantic tropical cyclone
Tropical cyclogenesis#Unusual_areas_of_formation
List of notable tropical cyclones#Unusual_landfalls
Medicanes - Mediterranean Hurricanes
Tropical like Mediterranean Storms - An analysis from Satellite


Thanks to thefullwiki.org for the information.