Klaus, was a European windstorm or cyclone which made landfall over large parts of central and southern France, Spain and parts of Italy in January 2009. The storm was the most damaging since Lothar and Martin in December 1999. The storm caused widespread damage across France and Spain, especially in northern Spain. The storm caused twenty-six fatalities, as well as extensive disruptions to public transport and power supplies, with approximately 1.7 million homes in southwest France and tens of thousands of homes in Spain experiencing power cuts. Severe damage to property and major forest damage was caused. Peak gusts were over 200 km/h; sustained winds of over 170 km/h (110 mph) were observed, which are hurricane-force winds.
The storm made landfall near Bordeaux, France, at 5:00 am Central European Time on Saturday, 24 January. It traveled southeastwards towards the south-east coast of France throughout Saturday morning, finally reaching there at 1:00 pm. It continued eastwards over Italy, but without causing significant damage. Low pressure systems are regarded as fairly common in Europe at that time of year. Some reports called it the storm of the decade; BBC meteorologist Alex Deakin said, "Saturday's storm is being described as the most damaging since that of December 1999 which killed 88 people."
Michèle Alliot-Marie, the French interior minister, stated that in addition to the 300 civil security agents located in the Landes region of France, another 715 agents would be deployed. In Bordeaux's Gironde region, 19 residents of a retirement home were evacuated by rescuers after the rooftop blew away. Authorities also evacuated campers from the pine forests in Les Landes. Thousands were evacuated from nearby housing estates in La Nucía, north of Benidorm in Alicante, as the Spanish Army helped to fight a forest fire, which was started by a felled electricity pylon. There were also forest fires in the region of Catalonia, while Spain put emergency services on high alert. Waves over 20 metres high were registered off the northern coast of Spain and dolphins were stranded on beaches in the region as a result of high winds. The storm left millions without electricity and fixed and mobile telephony, including 1-1-2. Solar panels and wind turbines were not used to provide emergency power and satellite telephony was not employed for emergency communications.
Parts of a sports center collapsed in Sant Boi de Llobregat, 11 kilometres (6.8 mi) south west of Barcelona, killing four children and injuring 16. In Burela, Galicia, a policeman was killed by a falling tree as he was directing traffic. In La Palma de Cervelló, Province of Barcelona, a road worker was killed by a falling tree. A woman died when a wall collapsed in Barcelona. A man was also killed by a collapsed wall in Aigües de Busot, in Alicante. A woman was killed after being hit by debris. A Portuguese captain died after being rescued in the northwestern port city of A Coruña, Galicia. A man died after falling from a roof due to the heavy wind.
A man was killed by a falling tree while driving near Mont-de-Marsan. A 78-year-old man died when he was hit by flying debris near his home and a 75-year-old man was found hit by a tree A woman died in the hospital in the département Landes after she has been found in her garden suffering of hypothermia.. In the Gironde département, a 70 year old woman died when her breathing machine failed because of the power outage. Two elderly people were killed in Nanteuil-Auriac-de-Bourzac, Dordogne, by carbon monoxide intoxication which also killed two people in Port-Barcarès, Pyrénées-Orientales.
The effects of the storm were felt from the Channel Islands south to Barcelona. The most damaging effects of the storm's rain and heavy winds were located in the south-west of France. The storm originated in the Bay of Biscay and tracked south-eastward through southern France during the evening of 24 January towards towards northern Italy and the Adriatic, where minimal damage was caused.