It is often called 'overdriving your headlights' when a driver's visibility is limited due to fog or darkness, but the driver still drives at a speed which does not allow them the ability to stop in time to avoid obstacles in the road.

Is it OK to overdrive your headlights?

Overdriving your headlights means not being able to stop inside the illuminated area ahead. It is difficult to judge other vehicles' speeds and distances at night. Do not overdrive your headlights—it creates a blind "crash area" in front of your vehicle. You should be able to stop inside the illuminated area ahead.

At what speed are you overdriving your headlights?

The math is surprisingly simple: At 55 miles per hour, you need about 500 feet to perceive an obstacle, react to it and bring your vehicle to a complete and safe stop. AAA's research found that the most common halogen reflector lights illuminate only 300 feet on low beams.