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Hurricane Debbie is the most powerful cyclone on record to strike Ireland in September, and possibly the only tropical cyclone on record to ever strike the British Isles while still tropical. The fourth named storm of the 1961 Atlantic hurricane season, Debbie originated from a well-defined tropical disturbance that was first identified in late August over Central Africa. Tracking generally westward, the system moved off the coast of Senegal on September 5 into the Atlantic Ocean. By this time, it was estimated to have become a tropical storm, but forecasters did not issue advisories on the system until two days later. Late on September 6, Debbie passed through the southern Cape Verde Islands as a strong tropical storm or minimal hurricane, resulting in a plane crash that killed 60 people in the islands. Once clear of the islands, data on the storm became sparse, and the status of Debbie was uncertain over the following several days as it tracked west-northwestward and later northward. It was not until a commercial airliner intercepted the storm on September 10 that its location became certain. The following day, Debbie intensified and reached its peak intensity as a Category 3 hurricane on the Saffir–Simpson hurricane scale, with maximum winds of 120 mph (195 km/h). Maintaining its peak intensity for over a day, the hurricane gradually slowed its forward motion and weakened. By September 13, Debbie's motion became influenced by the Westerlies, causing the system to accelerate east-northeastward. The system passed over the western Azores as a minimal hurricane on September 15. At this point, there is uncertainty as to the structure of Debbie, whether it transitioned into an extratropical cyclone or maintained its identity as a tropical system. Regardless of which took place, the system deepened as it neared the British Isles, skirting the coast of Western Ireland on September 16. Shortly thereafter, the system was confirmed to have become extratropical as it continued towards the northeast. The remnants of the storm later turned eastward, striking Norway and Russia, before dissipating on September 19. Striking Ireland as a powerful storm, Debbie brought record winds to much of the island, with a peak gust of measured just offshore. These winds caused widespread damage and disruption, downing tens of thousands of trees and power lines. Countless structures sustained varying degrees of damage, with many smaller buildings destroyed. Agriculture experienced extensive losses to barley, corn and wheat crops. Throughout Ireland, Debbie killed 18 people (12 in the Republic of Ireland and six in Northern Ireland). It caused US$40–50 million in damage in the Republic and at least £1.5 million (US$4 million) in Northern Ireland. The storm also battered parts of Great Britain with winds in excess of . ==Meteorological history== During late August and into early September 1961, an unusual series of low-level disturbances developed over Central and West Africa and into the eastern Atlantic Ocean. One of these systems, that probably formed over Central Africa at the end of August, became increasingly organized as it moved over Nigeria on September 1. As the disturbance travelled steadily westward, its mid-level circulation became well defined, and the accompanying low-level centre gradually followed suit. An upper-level anticyclone accompanied the storm during this entire period, providing a favorable upper-air regime for strengthening. According to a post-storm study in 1962, all the necessary environmental ingredients were available to the disturbance while it was over land; the only factor inhibiting earlier development was a lack of access to the warm waters. Around 1200 UTC on September 5, the low emerged off the coast of Senegal as a strong tropical depression or tropical storm. By this time, the system had a central pressure below 1006 mbar (hPa; 29.71 inHg), and sustained winds of 35 mph (55 km/h) were reported in Bissau, Guinea-Bissau. As the system neared Cape Verde, it continued to intensify and by the evening of September 6, reports from the nearby Danish tanker ''Charlotte Maersk'' indicated that the system was already at or near hurricane intensity. Late on September 6, Debbie passed over the southern Cape Verde Islands as a strong tropical storm or low-end hurricane.〔 Continuing on a west-northwest path, mainly in response to a large area of high pressure over the eastern Atlantic, the system continued to intensify. Sea surface temperatures in the region averaged , supportive of tropical development. At 1913 UTC on September 7, a picture from TIROS-3 showed that an eye had already developed and banding features covered an area more than from the centre.〔 Debbie was not classified operationally as a tropical storm until 2200 UTC on September 7, at which time the centre was estimated to be about west-southwest of Sal Island. Over the following three days, virtually no data was available on the hurricane and no reliable estimates on its intensity could be made. During this time, the storm was estimated to have taken a more north-westerly course over the open ocean. It was not until a KLM flight encountered the storm on September 10 that an accurate positioning of the hurricane could be made. After maintaining a nearly steady course for three days, Hurricane Debbie turned northward and slowed as it neared a break in the ridge previously steering it west-northwestward. During the evening of September 11, a United States Navy Aircraft reconnaissance mission into the storm found sustained winds of 110 – 120 mph (175 – 195 km/h) and a central pressure of 976 mbar (hPa; 28.82 inHg),〔 reaching its peak intensity as a modern-day Category 3 hurricane on the Saffir–Simpson hurricane scale with winds of 120 mph (195 km/h). After maintaining its windspeeds for over 24 hours, the system weakened and turned sharply towards the east-northeast in response to the upper-level westerlies.〔 By the afternoon of September 13, Debbie was again a Category 1 storm as it quickly accelerated towards the Azores. Early on September 15, the storm passed over the easternmost Azores with winds estimated at 80 mph (130 km/h) before turning more northeasterly.〔 Once past the Azores, there is an uncertainty over the structural changes that took place with Debbie. According to the United States Weather Bureau's preliminary report, the system acquired characteristics of an extratropical cyclone on September 15, though remained a strong system.〔 This conflicts with the best track supplied by the Bureau and the National Hurricane Center's hurricane database maintains the system as a tropical cyclone until the afternoon of September 16.〔 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 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 . 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.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hurricane Debbie (1961)」の詳細全文を読む スポンサード リンク
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