Cowley is entering his second professional season, after splitting his rookie campaign between the Manchester Monarchs and American Hockey League's Springfield Thunderbirds. The 23-year-old posted a 9-9-1 mark, a 3.15 goals-against average, a .902 save percentage and two shutouts with Manchester, while compiling 5-5-0 record, with a 3.13 goals-against average, a .901 save percentage and one shutout in 14 games with Springfield. He also appeared in four playoff contests with the Monarchs, going 1-1 with one shutout during their second round series against the Adirondack Thunder.
Prior to turning pro, the Evergreen, Colorado native attended the University of Denver for four years. Cowley finished with a goals-against average under 2.25 and a save percentage of at least .920 in all four of his seasons in Denver, while earning a 23-15-3 record. The Pioneers reached the NCAA Tournament each of his four seasons, led by the 2016-17 squad which won the NCAA National Championship. Cowley was selected by the Florida Panthers in the fourth round (92nd overall) of the 2013 NHL Entry Draft.