V-shaped storm hits Gard in 2021

In September 2021, the Gard department in France experienced an extreme weather event, with 260 millimeters of rain falling in three hours, including 138 millimeters in just one hour. This was caused by a rare type of storm known as a V-shaped storm.

Understanding V-shaped storms

These storms, called stationary multicellular storm systems, appear as a V shape on satellite images and can also look like a U or a ring. They are classified as mesoscale systems when they span more than 100 kilometers horizontally.

Intense rainfall from V-shaped storms

V-shaped storms can produce very heavy rainfall, with intensities reaching 50 to 100 millimeters per hour in certain areas. In the Gard event, a peak of 20.5 millimeters of rain fell in just five minutes, highlighting the storm's severity.

History of V-shaped storms in France

Such storms have occurred in the Mediterranean region multiple times, including in the Gard and Hérault departments in 2021, 2024, and 2026. Similar events have been recorded in Nîmes in 1988, Vaison-la-Romaine in 1992, and the Aude in 1999.

Recent V-shaped storm activity

In September 2024, a stationary storm hit the Fréjus Gulf. In 2026, Saint-Hippolyte-du-Fort recorded 337.6 millimeters of rain, leading to a red flood warning for the Gard and Hérault departments. Another storm in October 2026 caused 150 millimeters of rain in the Hérault hinterland, requiring emergency measures.

Risks and warnings from V-shaped storms

The main danger of these storms is the extreme amount of rain they can deliver in a short time, especially in coastal or Mediterranean regions. Authorities issue vigilance levels, which can escalate to red alerts during severe episodes, to help communities prepare and stay safe.