The 27-year-old Moroccan sealed a deadline-day move to the Riverside Stadium from Hibernian, but was not available for Saturday's 1-0 npower Championship defeat at Crystal Palace after returning home to apply for a visa.
However, Mowbray is confident his new signing can provide something different to the club.
He said: "Zemmama will give us something that the team doesn't have, a little bit of creative edge in the final third.
"All our strikers - Kris Boyd, Leroy Lita, Scott McDonald - have built their reputations on scoring goals rather than creating their own goals or having the ability to nutmeg somebody or play look-away passes or reverse passes that somebody doesn't see.
"I think Zemmama can bring that extra creative element to our attacking line, which will hopefully help the team."
Source: PA
Source: PA