Southern U.S. speech has been the focus of much sociophonetic work. In terms of vowel patterns, Southern speech is often characterized by the Southern Vowel Shift (SVS, involving shifts in /e/, /ɛ/, and /aɪ/), back vowel fronting, and changes in glide dynamics. The SVS, in particular, is said to play a primary role in distinguishing the South as a unique dialect region. However, there have been few investigations of the role of various vowel quality differences in perceptions of Southern accent, particularly across the vowel space beyond /e/, /ɛ/, and /aɪ/, or that ask whether any aggregate speaker-level acoustic measures align with listeners' perceptions, despite some suggestions in the literature to this effect. The current study examines what acoustic cues contribute to non-Southern listeners' evaluations of words spoken by Southerners as sounding more or less Southern accented, looking at a range of vowels from across the vowel space. Results indicate that listeners rate the speakers' productions of /u/ and /ɔ/ as most Southern and that vowel dynamics and speaker-level measures were the acoustic factors most predictive of Southernness ratings. These results together call for further work examining vowel dynamics and a more complete set of vowel categories in perception studies of Southern speech.