 As it approached the Lesser Antilles, a surface low developed, and with the confirmation of a closed low-level circulation from the Hurricane Hunters, it is estimated the system developed into Tropical Depression Five on August 24 about north-northwest of Grenada.Located to the south of a ridge across the southwestern Atlantic Ocean, the depression tracked west-northwestward through an area of dry air and westerly wind shear.Despite the shear, convection intensified near the center as banding features improved, and on August 24, the depression intensified into Tropical Storm Ernesto.