The shooting occurred at about 2:20 a.m. at Master's Donuts in the 300 block of East Baseline Street. Surveillance video shows the gunfire shattering the glass door and a window. Witnesses said dozens of shell casing littered the parking lot.
Six customers and two employees were inside when the shots were fired.
"I just (stayed) flat on the floor. I don't look, just ducked," one employee who did not want to be identified said.
The woman was shot in the right arm and was taken to a hospital.
No suspect information was immediately released.