Overview
- A brief but violent wind event around 17:45–17:50 centered on Ermont damaged roofs, uprooted trees and struck about a dozen nearby communes.
- Ten victims were recorded: one dead, a 23-year-old construction worker, four in critical condition and five with less severe injuries.
- Roughly 1,700 households lost power overnight with Enedis targeting restoration on Tuesday, and RER C plus Transilien H service was suspended between Pontoise and Ermont‑Eaubonne until 15:00.
- Crisis coordination and a gymnasium shelter were activated as approximately 80 firefighters, 50 police officers and 20 Samu personnel secured damaged areas and carried out evacuations.
- Workplace inspectors conducted on-site checks and the Ermont mayor said he will seek natural-disaster recognition, while meteorologists called the tornado exceptional and the first deadly one in France since 2008.