Deadly Cyclonic Catastrophe: Once-in-600-Year Storm in Libya Swept Entire Neighborhoods Out to Sea

Derna Libya Storm

A September 2023 cyclone severely impacted Libya’s northeastern coast, especially the city of Derna. Thousands perished, and 40,000 were displaced. Satellite imagery highlighted the immense damage, with the storm being classified as one of Africa’s deadliest and rarest weather events.

Flash floods in the port city destroyed roads and swept neighborhoods out to sea.

Heavy rain from a cyclone in the Mediterranean inundated cities along the northeastern coast of Libya in early September 2023, causing thousands of deaths. The port city of Derna (Darnah), home to about 90,000 people, was one of the worst hit by the storm and suffered extensive flooding and damage.

Derna Libya August 2023 Annotated

Satellite image of Libya’s northeastern coast captured on August 25, 2023, by the Operational Land Imager-2 on Landsat 9.

The images on this page show the city before (above) and after (below) the storm. The image below, acquired by Landsat 9’s Operational Land Imager-2 (OLI-2) on September 18, shows eroded banks of Wadi Derna near where it meets the Mediterranean. Water just off the coast appears muddier than in the image above, which shows the same area on August 25 and was acquired by Landsat 8.

Derna Libya September 2023 Annotated

Satellite image of Libya’s northeastern coast captured on September 18, 2023, by the Operational Land Imager on Landsat 8.

Tropical-like cyclones in the Mediterranean, or “medicanes,” develop only once or twice a year, according to NOAA, and typically form in autumn. According to meteorologists at Yale Climate Connections, this storm was the deadliest in Africa’s recorded history. A recent assessment by scientists at World Weather Attribution estimated that precipitation received by the region was a one-in-300 to one-in-600-year event.

NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey.