A truck driver was killed by a falling tree northeast of Paris and 1.2 million households in France were left without electricity. Authorities in Finistere, Brittany, urged people to stay at home and avoid winds which were hitting 207 kph, leading to reports of 20 meter waves off the coast.

“I repeat: stay at home,” local prefect Alain Espinasse told RTL radio.

Storm Ciaran, which follows on the heels of Storm Babet two weeks ago, was driven by a powerful jet stream that swept in from the Atlantic, unleashing heavy rain and furious winds that have already caused heavy flooding in Northern Ireland.

In Britain, the Channel Islands were among the worst hit areas, with the BBC reporting that windows had been blown in and one roof ripped off a house on Jersey, forcing families to move into nearby hotels.

Southern England was also badly affected, with many schools closed and the rescue charity that saves lives at sea urging people to avoid the coast.

“This rough weather could make visiting our coasts around southern England and Wales treacherous and bring very dangerous sea conditions,” Ross Macleod of the RNLI said.

Britain’s Met Office said Storm Ciaran was a “fairly normal” Autumn storm but said that under certain climate projections the frequency and intensity of such storms in the British winter could slightly increase.

Dutch airline KLM said it had also scrapped dozens of flights to and from Amsterdam Schiphol airport on Thursday.

(Reporting by Kate Holton in London and Dominque Vidalon in Paris; Editing by Angus MacSwan)