The driver of the southbound bus noticed the car and slowed to nearly a complete stop, while honking and waving at the woman.
The woman kept driving and hit the bus head-on, totaling the SUV and damaging the front of the bus and windshield, Carpenter said.
"We don't know why she drifted out of her lane," Carpenter said.
Salt Lake City police spokesman Dennis McGowan said that after the accident, the woman seemed alert and did not appear under the influence of alcohol or drugs. She did not mention any medical conditions or that she was distracted at the time of the crash, McGowan said.
The investigation is ongoing, but police said the woman who was taken to the hospital with minor injuries will be cited for driving left of center.
The bus driver and three bus passengers were uninjured, Carpenter said.
Per policy, the driver of the bus was placed on administrative leave and will undergo drug and alcohol testing.
Carpenter said it appears the SUV was traveling at, or less than, the posted 30 mph speed limit.