During that day, the trough developed a circulation centre near its northern end (Newfoundland), forming closed isobars around it which indicate a closed wind circulation and qualify the system as an extratropical cyclone. Hours after formation, the storm was caught by Fionn's strong jetstream and started moving to the east, posing a threat to Europe. While crossing the Atlantic, David once again lost some structural definition and opened up into a trough under the strong influence of Fionn. The weakened David was racing eastward through the North Atlantic, taking aim at the British Isles. Meanwhile, the ECMWF and GFS lowered their predictions concerning David's intensity as it was unclear if the system would be able to recover from the structural deterioration that was inflicted by Fionn. David would cross the North Atlantic in less than two days. While David was approaching Ireland in the evening of 17 January, Fionn started to weaken as its centre began to fill. David managed to redevelop a closed circulation while passing over the British Isles and the North Sea in the morning of 18 January, worsening the risks for Central and Eastern Europe. Britain received some hurricane-force gusts up to . Subsequently, the storm had some hours to gain additional energy while moving quickly over the North Sea before making landfall in the Netherlands. The cyclone's minimal pressure bottomed out at while centred over the North Sea, which was substantially lower than predicted by GFS and ECMWF. Vlieland, an island off the northern Dutch coast, where the storm made the first of its two landfalls in the Netherlands, experienced wind gusts up to . Moving on, the winter storm rampaged in Germany, disrupting public transport services as it already did in the Benelux and causing ten deaths on 18 January. While centred over Germany, the storm still was near peak intensity, having a central pressure between , and caused widespread gusts in the range, with gusts up to on mountains. During the evening of 18 January, the eastward moving centre of David crossed the Polish border and weakened to . David weakened to a regular low pressure area as its winds fell below storm force on 19 January. It continued its eastward motion through Belarus and the westernmost part of Russia. The southern flank of the low also affected the weather in Slovakia and Ukraine. On 22 January 2018, being located over western Russia, David merged with another weak low that was located over Scandinavia. Thus, David dissipated as a meteorological entity. David was a compact and fast-moving cyclone, which is typical for systems that are steered by strong Icelandic lows which develop a strong easterly flow on their southern side.