Rules of the Road: How to navigate flashing traffic lights

When do traffic lights flash? It can be when they are under maintenance, or the municipality is changing over the pattern, or even during the late hours of the evening into the early morning for ease of traffic flow. In Alberta, you’ll see two different flashing lights:

Flashing Yellow Light

Drivers facing a flashing yellow traffic control light may proceed with caution after yielding to pedestrians and other vehicles within the intersection. Opposing traffic will have a flashing red light.  

Flashing Red Light

Drivers facing a flashing red traffic control light must stop before the stop line or crosswalk. If there is no stop line or crosswalk, drivers must stop before the intersection. Drivers should proceed only when it is safe and after yielding the right-of way. The flashing red light is treated like a stop sign. 

• When the lights in all directions are flashing red the intersection becomes a four-way stop.

  
  

• If the power is out to the intersection and there are no lights, the intersection becomes a four-way stop.

It’s important to remember that many drivers and pedestrians do not know the rules of flashing traffic lights, so always drive defensively.

Source: Alberta Driver’s Guide Cars and Light Trucks Spring 2026 edition.