Soon after being reclassified as a subtropical storm, Leslie began to turn due to interactions with the subtropical ridge to the west and a large deep-layer low that was forming to the east. Over the course of a day, the storm turned from a westerly direction to the southwest.[15][16] At the same time, Leslie was acquiring more tropical characteristics. On 29 September at 21:00 UTC, it became fully tropical after developing an anticyclonic outflow to its northeast and southeast as well as in its main convective band.