Black ice is nearly impossible to see, can form almost anywhere on the road, and has the potential to send your vehicle careening into oncoming traffic. It’s bad news. Here’s how you can spot that nasty black ice and avoid accidents when you hit the road during the holidays.
What Is Black Ice?
In short, black ice is clear ice that forms on a black surface, like an asphalt road, and blends in so it’s hard to see. It’s dangerous because it can hide in plain sight, and cause you to lose control of your vehicle on busy roads. It can form several ways, including:
Snow melting during the day, making the roads the wet, then refreezing at night as clear ice.
Rainfall wetting the road and forming puddles before the temperature drops and freezes solid.
When moisture in the air condenses and forms fog or dew that then freezes on the road.
For it to form, the surface of the road must be at or below 32 degrees Fahrenheit. This means bridges and overpasses are particularly prone to having black ice since cold air can flow underneath and above the elevated road surface. The same goes for shaded areas on the road where the temperature will much lower than the spots being warmed by the sun.
How to Spot It
To spot black ice, it helps to know where it forms. As previously mentioned, be on the lookout for bridges, overpasses, bottoms of hills where water runoff can pool up, and anywhere that sunlight can’t get to, especially during the day. Also, heavily traveled roads are less likely to have black ice than rural or suburban roads. It’s important you know when to be watching for it too. Most black ice forms when the temperature dips, so from sunset to sunrise you should definitely be at full alert. Check your car’s thermometer to give yourself an idea of what conditions are like out there. Anywhere in the 40s and below (to account for gauge inaccuracy) is a danger zone.
But how do you spot something that’s so hard to see? At night, look for patches of pavement that are slightly darker and duller than the rest of the road. During the daytime, look for glossy, wet-looking surfaces in or around shaded parts of the road. Julie Lee, national director of AARP Driver Safety, suggests you take a close look at the pavement before you even get in your car. How does it feel? If it feels dry, but you see spots on the road that look dark and glossy, that’s probably black ice. If it’s wet and not frozen, there may still be black ice, but only on shaded areas.
You can also identify black ice conditions by watching the cars in front of you. Robert Sinclair Jr., a spokesman for AAA Northeast, suggests at the New York Times that you pay particular attention to other drivers’ tires. If the road is glistening like it’s wet and tires are spraying up water, there’s probably no black ice. If there’s no spray, watch for those dark patches.