Transfer the turkey to a serving platter, cover with foil, then set a large, thick towel over it to keep it warm.
Remove and discard the vegetables from the roasting pan. Place the pan on the stovetop over medium heat (you may need to use more than one burner). Bring the juices to a simmer. Add the white wine and scrape up any browned bits in the pan. In a small bowl, whisk together the chicken broth and flour.
Pour into the pan, whisking continuously. Simmer for 5 minutes, stirring constantly. Strain the gravy, if desired.