Nowell was the 43rd overall pick in the 2019 NBA Draft by the Minnesota Timberwolves after two seasons with the University of Washington.

In two seasons at the University of Washington from 2017-19, Nowell averaged 16.1 points, 4.6 rebounds, 2.9 assists and 1.2 steals per game while shooting 47.6 percent from the field and 39.6 percent from the 3-point line. As a sophomore in 2018-19, Nowell was named the Pac-12 Player of the Year after guiding the Huskies to the Pac-12 regular-season championship. As a senior, Nowell shot 44 percent from the 3-point line.