On September 2, a tropical wave entered the Atlantic basin from Africa, the latest of a long train of disturbances to do so. The system was quite disorganized, and matters were made worse for it by the presence of another wave nearby and a third several hundred miles further west. The two nearby waves merged south of the Cape Verde islands, while the third was moving little. Two low pressure areas near one another often begin to rotate cyclonically (counterclockwise) around one another by the Fujiwhara effect. This had the impact of shunting the combined wave around toward the northwest. The system it was rotating around dissipated by the 5th and atmospheric conditions for development became more favorable.
Nevertheless, our wave had multiple vortices associated with it. These sprialled inward over the next couple of days. Late on September 6, thunderstorm activity increased too and Tropical Depression Seventeen was designated. The center was still elongated southwest to northeast, but the broader circulation and banding were quite impressive. During the morning of the 7th, the depression became Tropical Storm Paulette. The new earliest "P" storm, it replaced Philippe of 2005, which formed on September 17 of that year. At the time, steering currents around Paulette were quite weak, and it did little more than drift northwestward that day.
The storm strengthened steadily throughout the next day as outflow improved, peaking at 65 mph sustained winds and a pressure of 995 mb. Wind shear from an upper-level trough increased out of the southwest by the later part of day September 8. This displaced convection northeast, eventually exposing the center of circulation and beginning a weakening trend. At the same time, the subtropical ridge built in from the north, which got Paulette moving a bit more quickly toward the west-northwest on September 9. This motion was a bit erratic but the storm generally stayed on the same heading for the next couple of days. Wind shear peaked in excess of 40 kt on September 10, but Paulette continued to generated impressive thunderstorm activity northeast of the center and weakening was only gradual.
Turning toward the northwest on September 11, the system passed through the area of highest shear and moved toward better atmospheric conditions and warmer water. This set Paulette on a strengthening trend once again. The cyclone's structure also changed significantly as the direction of shear shifted from out of the southwest to out of the southeast. Paulette had a bit of a "squashed" appearance, with large, healthy outflow channels to the west-southwest and east-northeast, but a small diameter in the perpendicular direction, once again due to the shear. This was now rapidly diminishing, however. It did not take long for Paulette to take full advantage: a clear eye appeared and the storm became a hurricane late on the 12th.
The storm spent the early part of the day on September 13 mixing some dry air out of the core, and it was successful. The eye became larger and more symmetric during the afternoon and intensification continued. Continuing northwestward, Paulette was aiming straight at Bermuda; conditions there began to deterioriate later that day. At the same time, the storm reached the western extremity of the subtropical ridge and began to recurve, turning toward the north. Paulette hit Bermuda directly before dawn on September 14, with maximum sustained winds of 90 mph and a minimum central pressure of 973 mb. Remarkably, arond 5 am local time, the entire island was inside the eye of Paulette. A little later, hurricane force winds again battered Bermuda as the southern eyewall came through.
The system continued strengthening as it turned northeastward away from the island, reaching category 2 status later that morning. Paulette achieved its peak intensity of 105 mph winds and a central pressure of 965 mb later on the 14th. Meanwhile, it was accelerating northeastward ahead of an approaching cold front. On September 15, ocean temperatures under the storm plunged; combined with the encroaching front, this began to induce extratropical transition and maximum winds decreased. The next morning, Paulette became extratropical. The remnants moved east and slowly weakened before veering south on September 17. Several days later, it passed west of the Azores and then south of them as it turned back toward the east under the influence of a trough over the northeastern Atlantic.
These movements had brought former Paulette over warmer waters again, enough for it to regain deep convection and once again become a tropical storm late on September 21. This classification was short-lived, though. Stable air and cooler water quelled any thunderstorm activity that had redeveloped and Paulette became a remnant low late the next day. The low then reversed course and moved west again. It finally dissipated several days later.
The above image shows Paulette as a category 2 hurricane over the open Atlantic.
Between when Paulette first became a tropical cyclone and its final transition into a remnant low, a remarkable seven named storms formed in the Atlantic: Rene, Sally, Teddy, Vicky, Beta, Wilfred, and Alpha.
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