KNOXVILLE, Tenn — Winter weather dumped several inches of snow across East Tennessee early Saturday morning, and temperatures continued dropping throughout the day. While the snow may have stopped, there were concerns snow that melted during the day could refreeze at night as black ice.
It happens when moisture is rapidly frozen over the roads, such as when a snowstorm stops in the afternoon and gives the snow a chance to melt during the day. When the temperature drops into the teens as night falls, the thin accumulations of water may quickly refreeze in spots on most roads.
It can be dangerous for drivers, and black ice can even form on sidewalks. Usually, the ice may not even have bubbles in it, making it hard to spot.
Black ice usually forms late at night and early in the mornings, when the sun is not out. It also usually forms in areas where there is colder air, such as over bridges.
If drivers hit a patch of black ice, they may panic. It's important not to hit the brakes though — slamming on the brakes could cause a person to lose control of their car.
Instead, drivers should gently ease off the accelerator and make sure to keep the steering wheel straight. If they start to slide, drivers should turn the steering wheel in the direction of the slide to stay in control.
Then, when drivers are back on the road and away from the ice, they can consider finding another, safer route.
And the best thing drivers can do to stay safe on the road is simply slow down if black ice is a possibility. Experts said icy roads can cause cars to have around 50% less traction than normal. So, drivers should go at half the speed they normally do if they think there may be black ice on the roads.
Drivers should also leave around 3 - 6 seconds worth of following distance between the car in front of them. That way, they have time to respond in case they run into trouble.
Officials said crews with the Tennessee Department of Transportation were clearing roadways and would work shifts through the night to make sure all routes were clean. They said they will also watch for roads that may refreeze during the night.