Hurricane Helene was the ninth named storm, as well as the fourth hurricane of the 2006 Atlantic hurricane season, as well as the second major hurricane of the season, following Hurricane Gordon. Helene was operationally classified as a Category 3 hurricane with 125 mph winds at its peak, though post-season analysis indicated that Helene only had winds in excess of 120 mph at its peak. Helene formed from a tropical wave that exited the coast of Africa in the second week of September. Helene moved through the central Atlantic Ocean, never affecting any land areas, eventually recurving out to sea. The only land area affected by Helene was the northern British Isles, where Helene caused minor effects as an extratropical storm.
There are no reports of damage with Helene, and there are no reported fatalities as a result of Helene.
|Formation||September 12, 2006|
|Dissipation||September 24, 2006|
|Highest winds||120 mph|
|Lowest pressure||955 mbar|
|Areas affected||Northern British Isles|
During the second week of September, a strong and well-organized tropical wave moved off the coast of Africa. On September 11, the National Hurricane Center had stated that the wave could quickly become a tropical depression before it even moved off the coast, due to the impressive organization of the wave. Once the wave came off the coast, it strengthened into Tropical Depression Eight on the morning of September 12. The depression would struggle to intensify at first, because of some easterly wind shear, as well as the Saharan Air Layer to the north affecting it. Finally, the large size of the depression also contributed to its lack of intensification. However, on September 13, banding features became better defined, and that evening, the depression was upgraded to Tropical Storm Helene. Helene was west of the Cape Verde Islands at this point, and Helene tracked west-northwest, while slowly intensifying over the warm waters of the eastern Atlantic Ocean. On September 14, the dry Saharan Air Layer continued to prevent development, with Helene remaining a low-end tropical storm. On September 15, as wind shear over the system decreased, Helene underwent a bout of intensification, which led to Helene strengthening to a 70 mph tropical storm.
On the morning of September 16, Helene started to develop a ragged eye, and thus became Hurricane Helene. Helene's intensification would level off for a while as a Category 1 hurricane, due to the influence of moderate upper-level wind shear affecting the system. Late on the evening of September 16, Helene began to intensify again, and by September 17, Helene had intensified rapidly, becoming a Category 2 hurricane, with the eye becoming clearer and deep convection surrounding the eye. Helene then turned to the north, slowing down in the central Atlantic Ocean, due to a weakness in the subtropical ridge further north that was created by Gordon to the north. On the evening of September 17, Helene intensified into a major hurricane with winds in excess of 115 mph. After that, Helene intensified a bit more, peaking as a 120 mph Category 3 hurricane early on September 18 (operationally, Helene was thought to have intensified further into a 125 mph Category 3 hurricane, but post-season analysis indicated that this did not occur). Also, at this point, Gordon and Helene were at basically the same longitude in the open oecan.
Gordon moved eastward on the afternoon of September 18, and at that time, a narrow ridge built in, which forced Helene westward. The eyewall of Helene then collapsed a bit, thus weakening Helene to a Category 2 hurricane. The collapse of the eyewall was a result of a long eyewall replacement cycle that Helene had undergone. On September 20, Helene turned to the northwest and weakened slightly because of an increase in wind shear over the system. That afternoon, Helene was downgraded to a Category 1 hurricane. Early on September 21, Helene moved to the north as it moved along the northwest periphery of the subtropical ridge. That evening, Helene began to turn to the northeast along the edge of the subtropical ridge to the east of Bermuda. Warm waters of around 81°F (27°C) kept Helene's strength about the same. On September 22, Helene strengthened slightly. After that, Helene accelerated to the northeast in the north Atlantic Ocean. Early on September 23, a QuikSCAT Satellite pass revealed that Helene was a strong Category 1 hurricane with 90 mph winds.
That afternoon, Helene transitioned into a hybrid storm, with both tropical and extratropical characteristics, having a deep warm core, as well as an asymmetric, frontal-like appearance. Wind shear then increased over the system again, weakening Helene. Helene remained a hurricane-strength storm until September 24, when it transitioned into an extratropical storm. After Helene became extratropical, it tracked eastward and became a gale center west of Ireland on September 27. Late on September 27, Helene merged with a larger extratropical low near the northern end of the British Isles.
Helene never affected any land areas while it was tropical. However, three ships were caught in Helene's path. The highest winds reported from those three ships was of sustained winds in excess of 56 mph in the north Atlantic on September 23. As an extratropical storm, Helene brought strong wind gusts were reported in Ireland and Scotland, areas just hit by Gordon earlier in the season. In Ireland, the strongest reported wind gust was 56 mph at Valentina Observatory. In Scotland, the strongest wind gust was on South Uist Island in the Outer Hebrides, with gusts as high as 74 mph being reported there. No reported fatalities, and no reports of damage existed with Helene.
Lack of Retirement
Due to its extremely minimal effects, the name Helene was not retired in the Spring of 2007, and is on the list of names to be used for the 2012 Atlantic hurricane season.