In New Orleans, there is a white, working-class dialect of English, sometimes called “Yat”, that has several notable similarities with that of New York City. These similarities have been argued to be the result of 19th-century dialect contact between residents of the two cities. This paper examines the palm vowel in New Orleans and argues that it too shows evidence of diffusion from New York around this time period. Words of the palm lexical set that have been part of the English lexicon since before the 19th century, such as father and calm, are found to be merged with the thought phoneme in New Orleans, while more recent palm words such as garage are merged with lot. A handful of traditional lot words, such as John and god, are also sporadically attested with the thought phoneme. Since traditional New York City English also possesses a palm vowel backer than lot, with words such as John and god variably included in it—a pattern that is not widely found in other dialects closely connected to New Orleans English—the findings are interpreted as further evidence for dialect diffusion from New York to New Orleans.