Ross, who made 13 starts this season, learned this week he needs Tommy John surgery.
Turner, a former first-round Draft pick of the Tigers in 2009, has made two starts and 16 relief appearances for the Nationals this season, pitching to a 5.08 ERA in 39 innings. He went 0-1 with an 11.74 ERA in two starts for Syracuse after being outrighted July 3.
If the Nats decide to give the ball to Jackson on Tuesday, Turner could provide relief depth prior to that as the club waits for newly acquired relievers Sean Doolittle and Ryan Madson to arrive.