 The system moved towards the British Isles and began to deepen. Debbie eventually brushed the coast of Western Ireland near Achill Island during the morning of September 16 with sustained winds of 80 mph (130 km / h). Around this time, a pressure of 961.4 hPa (28.39 inHg) was measured as it passed near Belmullet. If the system maintained tropical characteristics at this time, it would have been the first such storm on record to strike Ireland. Shortly after striking Ireland, the system was confirmed to have transitioned into an extratropical cyclone as it re-emerged into the northeast Atlantic Ocean. While passing between Ireland and Scotland, the system continued to deepen, achieving an estimated central pressure of 950 hPa (28.05 inHg). According to a study by Hickey and Connolly-Johnston, this ranked Debbie as the most intense post-hurricane from 1960 to 2012 to move through the British Isles. After clearing the United Kingdom, the hurricane's remnants turned more easterly, later impacting Norway and Russia before dissipating on September 19.
