Jooris went undrafted as an 18-year-old but attracted attention from NHL teams after playing for Union College and signed with the Calgary Flames after 2012-13, his junior season. The Flames sent him to the American Hockey League, where he had 27 points (11 goals, 16 assists) with Abbotsford in 2013-14.
Jooris had a good training camp before the 2014-15 season and was one of the final cuts, but early-season injuries led to the Flames recalling him on Oct. 16, 2014. He made his NHL debut one night later and scored a goal in a 3-2 loss to the Columbus Blue Jackets. Jooris finished with 24 points (12 goals, 12 assists) and received a qualifying offer from the Flames. But after he dropped to 13 points (four goals, nine assists) in 2015-16, the Flames opted not to re-sign him.