A 3.0GPA is not going to cut it without some amazing thing to improve your chances. You might have a chance, but, based on what you stated, your chances are not very good. Try your hardest to bring up your grades.
If the academy doesn't work out there is also AFROTC, the academy prep school, or the falcon foundation scholarship. The prep school and falcon foundation scholarships are awarded to some academy applicants who did not make the cut but still show a lot of potential. AFROTC is a separate program at civilian colleges that leads to commissioning as an officer. Some people will attend another college for a year or two before reapplying to the academy. This lets them build a better academic record. You may want to consider these if the academy doesn't accept you the first time. AFROTC would be good to apply for in conjuction with a civilian college if you do not want to wait the extra year or two of the other plans.