During what weather conditions is it crucial to adjust your driving speed?

Adjusting your driving speed during foggy conditions is crucial due to the significantly reduced visibility that fog creates. When fog is present, the ability to see other vehicles, road signs, and the road itself can be diminished, making it difficult to react appropriately to changing circumstances. Slowing down allows for more time to assess the situation and make safe driving decisions. Additionally, wet or slippery road surfaces can accompany fog, further necessitating a slower speed to maintain control of the vehicle.

In sunny weather, visibility is generally good, and while caution is always necessary, there typically isn't the same urgent need to adjust speed for safety as there is in fog. Driving during daylight usually allows for clearer views of the road, making it easier to navigate without the need for significant speed adjustments. Nighttime can pose visibility challenges as well, but the inherent characteristics of fog create a unique and more immediate risk that requires an even greater reduction in speed for safety.