Increasing upper-level westerlies caused Alberto to weaken as it moved east-northeastward, with the cyclone losing most of its convection. Early on August 14, Alberto was downgraded to a tropical storm. A westerly trough that had been guiding Alberto outran the storm, and strong ridging developed to the north and west. As a result, Alberto turned southward on August 15, southwestward on August 16, and then to the west on August 17. While curving northwestward and then northward, Alberto began to re-strengthen, and was upgraded to a hurricane for a third time on August 18. Alberto reached a third peak intensity as a Category 2 hurricane with winds of 105 mph (205 km/h) on August 20. After weakening back to a Category 1 hurricane, Alberto conducted an unusually large cyclonic loop, spanning approximately 5 degrees latitude and 8 degrees longitude. The cyclone was downgraded to a tropical storm on August 23, shortly before completing its extratropical transition. Although it did not affect land while tropical, the precursor tropical wave caused light rainfall in Senegal. The remnant extratropical cyclone also likely produced tropical storm-force winds in Iceland and Jan Mayen.