From Sahih Bukhari (Hadith 7040):
Narrated Salim's father:The Prophet (ﷺ) said, "I saw (in a dream) a black woman with unkempt hair going out of Medina and settling in Mahai'a. I interpreted that as (a symbol of) epidemic of Medina being transferred to Mahai'a, namely, Al-Juhfa
Reference: Bukhari 7040