Yes, They're Both Yellow Arrows

Flashing yellow cycle, substituting for green cycle Steady yellow cycle, normal

Along the Embarcadero southbound in San Francisco, there are still some left-turn lanes. Some of them have the standard green arrow for protected left turns, but at least two of them don't. Instead, they have a flashing yellow arrow where the green arrow would be for protected lefts.

The caution phase is still a standard yellow arrow in the center position, and there is a standard red arrow when turns are prohibited.

This signal is at Townsend Street. The left turn here is into a parking lot along an otherwise unused pier. Other flashing lefts are for left turns into driveways.

Note that the advisory sign indicates that left turns and U-turns are allowed only when there is a flashing arrow.

These photos were taken in August 2006.