The cable car was headed downhill on California Street passing through Chinatown when a driver changed lanes in front of the cable car about 8:30 a.m., Muni spokesman Paul Rose said.
The operator pulled the emergency brake but was unable to stop the cable car from hitting the vehicle, Rose said.
One person inside the car was hurt and was taken to a hospital with injuries that did not appear to be life-threatening, he said.
Rose noted that wet weather affects cable cars’ braking time.
“Any time there’s rain involved and cable cars going down a hill, it does take longer to stop,” he said. “People should be aware of that and create extra space between their vehicle and the cable cars in wet weather.”
Rose said the incident was cleared about 9:20 a.m.