Thousands of homes remained without power on Saturday after a fierce storm knocked out service for hundreds of thousands of people in Ireland and Scotland, the aftermath of a weather pattern that previously delivered bitter cold and record-breaking snow to parts of the United States.

The storm, which is named Eowyn, brought damaging gales throughout Friday, and 625,000 homes and businesses in Ireland were without power by the evening, the power supplier ESB said in a statement. On Saturday, the company said it was still assessing the extent of the damage.

The storm also knocked out power to hundreds of thousands of homes in Scotland, and prevailing winds made it nearly impossible for engineers to restore power to some regions, Scottish and Southern Electricity Networks, a regional energy supplier, said.

On social media, the energy company said that “it’s simply not safe right now for our teams to climb and carry out repairs to damaged poles and overhead lines.” As it worked to restore power to roughly 48,000 homes, the company offered hot meals to affected communities on Saturday.

By early Friday, the storm had already brought record winds to the Irish coast. At 5 a.m., a gust of 114 miles per hour was recorded at Mace Head, County Galway, beating a previous national record of 113 m.p.h. set in 1945.

The winds were so strong that they apparently disrupted some efforts to report them: “Severe winds have interrupted data supply from our stations in Belmullet, Mace Head and Markree,” Met Éireann, the Irish weather service, said on social media.

ESB Networks, a state-owned power company, said on Friday morning that “extreme, damaging and destructive” winds had caused widespread disruption to Ireland’s electricity network.

More than 560,000 customers were without power as of 6 a.m., it said. That is almost a quarter of the around 2.4 million total customers ESB Networks lists on its website.

The intensity of Storm Eowyn also prompted Britain’s Meteorological Office to issue its most severe red wind warnings for Northern Ireland and central and southwestern Scotland. It warned of “very dangerous conditions with widespread disruptions and significant impacts.” It was the first red wind warning issued for Northern Ireland since the Met Office moved to impact-based warnings in 2011.Paul Gundersen, a chief meteorologist at the Met Office, said, “We reserve the issuing of red warnings for the most severe weather which represents a likely danger to life and severe disruption, and that is the case with Storm Eowyn.”

The Irish meteorological service had issued equivalent top-level wind warnings for all of Ireland on Friday.

The Met Office has been naming strong storms during the autumn and winter seasons since 2015 along with Met Éireann and the Royal Netherlands Meteorological Institute. This storm’s designation, a name it shares with a “Lord of the Rings” character, was chosen by the Dutch weather service, which took suggestions from members of the public.

The stark temperature contrast created by the arctic blast that has gripped the United States in recent days and the warm moist air in the Gulf of Mexico intensified the jet stream, a high-altitude current of fast-moving air that drives global weather patterns west to east, and often plays an active part in the weather of Ireland and Britain.


The speed of the jet stream is usually 190 to 220 m.p.h., but this past week, it strengthened to about 260 m.p.h. This strengthening deepened Storm Eowyn rapidly in the Atlantic, steering it toward Ireland and Britain with heightened ferocity.

Eowyn is the most severe storm to hit Ireland since 2017, when one of the most powerful storms ever recorded in the northeastern Atlantic killed at least three people. The last time Britain experienced a storm of this strength was at the start of December with Storm Darragh, which was also influenced by a strong jet stream. Wind speeds for that storm reached 93 m.p.h. in Wales.

The jet stream is also known for powering trans-Atlantic flights, which pilots sometimes use to speed up journeys and save on fuel. On Wednesday, the ground speed of a flight from Las Vegas to London hit 814 m.p.h., close to the subsonic speed record of 835 m.p.h., which was set by a flight from New York to Lisbon last February.

In the United States this past week, the bitter arctic air mass plunged much of the country into dangerously cold conditions, delivering record-breaking low temperatures not experienced in decades, and life-threatening wind chills.

Eowyn is expected to clear into the Norwegian Sea on Saturday, allowing a brief lull of drier and calmer conditions for the day. Another storm system is forecast to bring similar hazards for Britain on Sunday and Monday.