By Matthew Brown and Omar R. Valdimarsson April 17 (Bloomberg) — European airlines canceled more than 70 percent of their flights today as most of the continent’s northern and central nations remained closed to air traffic, and Accuweather predicted little change until April 22. No flights will operate out of the U.K. until at least 1 a.m. London time tomorrow, the National Air Traffic Service said today via e-mail. The European Organisation for the Safety of Air Navigation, or Eurocontrol , expects about 6,000 flights across Europe today, compared with 22,000 on a “normal” Saturday, it said today in a statement. “Expect ongoing interruptions for the next four or five days,” Teitur Atlason, at the Icelandic meteorological office , said in a telephone interview today. “The eruption is still in full swing, and the volcano is spewing pretty dark ashes as high into the air as 5 to 6 kilometers.” More than 20,000 flights have been grounded after an April 14 eruption of the 1,666-meter (5,466-foot) Eyjafjallajökull volcano sent dust billowing across thousands of miles of European airspace and closed terminals from Dublin to Moscow. “The jet stream winds, which extend from 10,000 feet up to 40,000 feet, show no signs of change through Wednesday,” Accuweather said in a statement. “Any ash plume that is released from the Eyjafjall volcano in Iceland will continue to threaten northern Europe and the British isles.” Canceled flights are costing carriers about $200 million a day, the International Air Transport Association estimates. Anyone hoping to travel should contact their airline before traveling to the airport, NATS said. Fine Material Flights have been halted because of concerns that the ash plume could damage engines and speed sensors. The finest material from the blast is formed of dust akin to glass, which can melt and congeal in a turbine, causing it to stop, said Sue Loughlin , head of vulcanology at the British Geological Survey. “The current in the height the ashes are reaching remains a strong northwesterly wind, which blows the ashes to Scotland and South Scandinavia,” Atlason of the Icelandic Met Office said. “Once the ashes reach those places other more complex wind systems take over, which spread the ashes across North and Central Europe. This will continue until Wednesday.” Volcanic eruptions may continue for months, disrupting European air traffic when ash is blown above the continent’s busiest airports, Sigrun Hreinsdottir, a geophysicist at the University of Iceland, said in a telephone interview from Reykjavik. “From what we’ve seen, it could erupt, pause for a few weeks, and then possibly erupt again.” Last Eruption The last eruption of Eyjafjallajökull in December 1821 continued until January 1823. The current blast has sent ash to as high as 7 kilometers (4.5 miles), according to Gudrun Larsen, a vulcanologist at the University of Iceland. The magma had to pierce 200 meters of ice before erupting, she said. “We really don’t know if this eruption is going to last as long as the previous one, but we can’t say it’s not a possibility,” Larsen said by telephone. “This is the first time all our planes are grounded,” Lufthansa spokesman Wolfgang Weber said via telephone. British Airways Plc , which halted flights from the U.K. from midday on April 15, said at midday today that no services to and from London will operate today or tomorrow. Its shares tumbled 3.1 percent in the U.K. capital yesterday, the most since Feb 12. Canceled Flights Ryanair Holdings Plc , the region’s largest discount carrier, canceled all flights to and from the U.K., Ireland, Scandinavia, Belgium, the Netherlands, northern France and Germany until 1 p.m. on April 19. The stock fell 2.5 percent in Dublin, the steepest drop since Feb. 5. Deutsche Lufthansa AG canceled all flights to and from German airports until 8 p.m. CET tonight, it said in a statement on its Web site. Air Berlin Plc canceled all flights except some connections in Spain until 2 a.m. CET tomorrow. Passenger were asked not to travel to the airports. Denmark extended the shutdown of its airspace for all flights until 2 a.m. local time tomorrow, according to the Web site of Copenhagen-based Naviair, Denmark’s flight controller. Switzerland and Belgium today extended closure of their respective airspaces to 8 p.m. local time, Agence France-Presse reported. Paris airports will remain shut until 8 a.m. on Monday, a government official said. Belarus closed airspace for passenger and cargo flights, Interfax reported. The ash may stay over the country for two or three days, it said. Amsterdam Airspace Air France-KLM Group’s Dutch KLM unit canceled today’s flights into and out of Amsterdam Airport Schiphol, the company said in a statement on its Web site. The Dutch airspace be closed its airspace until further notice, Amsterdam Airport Schiphol said on its Web site, citing a decision by the Netherlands’ Inspectorate for Transport, Public Works and Water Management. The airport said it wasn’t clear when traffic might resume. Carriers throughout the Asia-Pacific region canceled flights on the routes to Europe, with Australia’s Qantas Airways Ltd. saying it didn’t know when service might resume. Cathay Pacific Airways Ltd. , based in Hong Kong, scrapped departures to London, Paris, Frankfurt and Milan and said it wouldn’t accept new bookings for the next few days. Europe-bound flights from Japan, South Korea, China and India were stopped because of danger from the ash, with Air India and Singapore Airlines Ltd. also canceling some routes to North America. ‘Several Days’ “At this stage it’s highly unlikely things are going to return to normal for several days at least,” David Epstein , a Qantas spokesman in Melbourne, said today at a press briefing. “It may well be a week.” Prevailing winds may provide some respite for travelers. Air streams over Britain come from the west or southwest 70 percent of the time and would carry ash away from the major hubs such as Heathrow and Amsterdam Schiphol, said Barry Grommett , a meteorologist at the U.K. Met Office , the government forecaster. “We normally look to the Atlantic for our weather, so that’s going to move anything emitting from a volcano in Iceland away from us,” he said by telephone. “The predominant pattern would take the plume north-eastward from the eruption site.” Blocking Pattern The outlook this weekend is for westerly winds to pick up over northern Britain, shifting ash away from Scotland, while a blocking pattern may continue to keep it over England. The edge of the ash cloud was forecast to reach as far south as northern Italy and Romania and as far east as the borders of Kazakhstan as of 6 a.m. today London time, according to the Met office. Because of the wind direction Iceland’s Keflavik remains open, with North American flights operating on schedule. Hubs serving 2 million people and 48 percent of Europe’s air traffic have been affected by the disruption, the Airports Council International industry group said yesterday in a statement. The situation was changing “every few hours,” it said. “This is a new situation for us,” Joe Sultana , director of airspace, network planning and navigation at Eurocontrol, which oversees the region’s flight paths, told reporters in Brussels yesterday. “We understand the economic impact to both the airlines and the European economy, but safety comes first.” The Icelandic eruption began on March 20 with a lava flow on the eastern flank of the Eyjafjallajökull volcano, according to the Institute of Earth Sciences at the University of Iceland. After a lull, it erupted again early on April 14, directly under the icecap that covers most of the mountain. Magma and Ice “The problem here is we have magma interacting with glacier ice and that leads to explosions,” Hreinsdottir said. “That causes the material to go much higher in the air.” Mike Burton, a researcher at the Italian National Vulcanology Institute who has studied the ash from the latest explosion, said it presents more of a threat to aircraft than would the dust from a typical eruption. “It’s likely that ash production will continue long after all the ice is melted in the volcano as this kind of magma can produce ash without water,” Burton said by telephone. “Fine ash is easier to transport long distances and goes higher into the atmosphere, so this is not good news for flights.” To contact the reporters on this story: Matthew Brown in London at mbrown42@bloomberg.net ; Omar R. Valdimarsson in Reykjavik valdimarsson@bloomberg.net