Winter storms wreak havoc on highways and arterial roads. Even the slightest amount of freezing rain or mist may create a dangerous road situation called black ice, a thin coating of ice that is often invisible to drivers. Vehicles that hit black ice unexpectedly and at high speeds may have trouble stopping or staying on course to avoid a crash. Snow also causes problems as it leads to slushy and uneven driving surfaces. Snow-covered roadways can make it difficult for drivers to determine the lanes and boundaries for a road. Heavy snow and blizzard conditions can also be difficult to drive through because of reduced visibility and quick accumulation.
Rain reduces traction on roadways and makes it difficult for drivers to retain control of their vehicles. Even light rain can mix with oils already on the road and create a hazard. Heavy rain reduces visibility and causes drivers to make speed adjustments that other drivers may not expect. Flooding can shut down roads, and people who do not heed flood warnings or who try to drive through roads during a flash flood put themselves in danger. Storms that include hail can also cause problems by distracting motorists or even cracking windshields in extreme situations.
High winds can cause vehicles to drift into adjacent lanes. It may be more difficult for drivers to control the steering and stay on an intended path. Wind can also introduce debris onto roadways, blocking visibility or requiring drivers to maneuver around large objects at high speeds. Dense fog reduces visibility, and in winter weather freezing fog may occur, hiding patches of ice or snow.
