Medicanes
The recent sea surface temperatures in the Mediterranean have been incredibly high, sparking some concerns about rapid cyclogenesis and medicane formation in the region. Although the chances of this happening have now greatly reduced what is a medicane and how are they formed?
The process begins when relatively cooler air from the European continent enters the Mediterranean region, where the warm sea surface acts as an energy source for convection. This rapidly warms the air just above the surface, whilst leaving the air aloft a bit cooler, increasing the lapse rate and therefore the instability. Over time, the convection releases heat to the top of the system, gradually generating a warm-core cyclone. This hurricane-like formation process has led to these storms being called medicanes (Mediterranean hurricanes) [1].
Despite their name, the comparatively small amount of warm water available for heating means that medicanes have a shorter lifespan and a lower maximum intensity than full blown tropical storms (hurricanes) [1]. In fact, Medicane Ianos in 2020 was the most intense medicane ever recorded, peaking at Category 2 hurricane strength. A medicane typically only maintains tropical storm status for around 24 hours before losing its tropical storm attributes, but this may reach 72 hours for some storms. Medicanes are also relatively rare, and form during the autumn and winter months whilst sea surface temperatures in the Mediterranean are still warm enough to kick-start convection [1].
The main impacts from a medicane are from their high volumes of rainfall, despite wind speeds still reaching disruptive speeds. Medicane Daniel, for example, was a storm that formed on the 4th of September 2023. It brought a massive amount of rainfall for parts of Greece, with over 700 mm recorded in just 18 hours! Libya saw its record highest daily rainfall of 414 mm, and unfortunately due to large infrastructure failures suffered significant fatalities [2,3].
More recently, Storm Samuel was named on the 15th of March 2026 and impacted large areas of the Iberian Peninsula. Four people were injured due to 100mph wind gusts. This occurred before it moved out over the Mediterranean and developed into a medicane. It then made landfall in Libya on the 18th of March [4,5].
Although these storms are rare, they can often bring severe impacts to the local population in the areas affected, and with many holiday destinations in the region, it is important to stay vigilant and up to date with any developing systems. With Mediterranean sea temperatures still incredibly high and the season only just beginning, there is a chance another medicane can form in 2026.
References and Further Information
[1] https://skybrary.aero/articles/medicane
