Academic journal article will have novelty in the subject matter which has not been reported. It can be refereed article . However , professional magazine articles may be known facts , data reported or compiled. It may not be refereed .It can not be a research article .
The differences will depend on may things. I agree that levels of peer review would have once been the difference - but you can now get journals (especially new open-access journals - that have questionable peer review - if any) versus established professional magazines that have good editorial review. As Ishmael suggests - you really have to be more specific.