Born in Los Angeles in 1949, Thow initially studied flute and piano, as well as composition with Adolph Weiss, Frank Salazar and Ingolf Dahl. He received a bachelor's degree from the University of Southern Californa in 1971 and a Ph.D in composition from Harvard, where he studied with Earl Kim and Leon Kirchner. He later went to Italy on a Fulbright fellowship to study with Luciano Berio, Luigi Dallapiccola and Franco Donatoni.

He joined the Berkeley faculty in 1981 and was chairman of the music department from 1991 to 1992.

According to the Times, Thow's music "combined a modernist's approach to rhythm and harmony with an almost Romantic lyricism, and often — in works like Trilce (1992) and Breath of Sun (1993) — the music's interest lies in the tension between those contradictory impulses."

Thow also incorporated Native American music into scores such as Lene Tawi (1996), a chamber orchestra setting of a Hopi rain song. His Chumash Songs (2000) used rhythms from the Chumash Indians of Southern California, while his Three Echoes (2001) is scored for a type of flute played by the Lakota Sioux.

In addition, Thow's catalogue includes: an opera, Serpentina (1999), based on a story by E. T. A. Hoffmann; music for a production of Shakespeare's Much Ado About Nothing (1989); and a dance work, Rim of Heaven (1984). He also wrote works for solo voice and chorus and music combing Baroque and modern instruments.