Cassandra Wilson, a Grammy Award-winning jazz singer and songwriter rooted in the blues tradition of her native Mississippi who became one of the most distinctive voices of her generation, died on Wednesday in Jackson, Miss. She was 70.

Jeramiah Howard, the coroner for Hinds County, which includes Jackson, confirmed the death. No cause was provided. One of the major jazz acts of the 1980s and ’90s — she opened for Miles Davis and toured with Wynton Marsalis — Ms. Wilson was a top-selling recording artist who preferred to call herself a musician, as opposed to being categorized solely as a jazz singer.

With a low and smoky voice, she brought suave romance to standards from the Great American Songbook, but she also embraced covers of artists including Joni Mitchell, Van Morrison, Neil Young and the Mississippi bluesman Robert Johnson. She wrote the words and music for original compositions on albums like “Blue Light ’Til Dawn” (1993) and “New Moon Daughter” (1995), the second of which received a Grammy for best jazz vocal performance and sold more than 400,000 copies.

She first gained recognition after working with the M-Base collective, led by the alto saxophonist and composer Steve Coleman. She later collaborated with other avant-garde figures, like the saxophonist David Murray. At the same time, she remained deeply rooted in jazz and other forms of African American music. A complete obituary will be published soon.