What is black ice and how do I discover it?

Written by Boel Haglund,

Black ice on the road is rightly considered very dangerous when driving. Still, many drivers are not watchful enough in weather conditions where there is the risk of black ice. But, what is this black ice – and what should I know about it?

No, it’s not black

Typically, black ice is invisible. It’s a thin coating of glaze ice on the road surface. Since it’s thin and transparent, the black road surface is clearly seen through it, and that is why it’s called blackice.

But, it’s dangerous

The typically low levels of noticeable ice pellets, snow, or sleet surrounding black ice means that areas of the ice are often practically invisible to drivers. Accordingly, the driver is not prepared of the slippery road area, and there is a risk of unexpected loss of traction. This in turn may result in subsequent accident.

Black ice sometimes forms from super-cooled rain which freezes into ice and constitutes a particular risk to winter traffic because it is extremely slippery and hard to spot. The temperature may be above freezing but the road surface may still be slippery.

The road surface can be well below freezing temperature – while the vehicle thermometer suggests it is not freezing.

This is how you discover black ice

Roads alongside open water are high-risk areas. Wind and high atmospheric pressure can quickly make the road slippery. All bridges, even those not close to open water, are cooled from above and below, which increases the risk of ice. On bends and in open spaces, the roadway may be covered by a thin layer of transparent ice when the wind blows

  • If the air is just above freezing, the road is damp and the weather clearing, there is a risk of the road freezing quickly when the temperature drops. The road surface is often colder than the air, which is good to keep in mind when the vehicle thermometer suggests it is not freezing.
  • Listen to the spray from the tires. If they have been making a wet and splashy sound and suddenly go quiet, this generally means that the moisture has frozen into ice.
  • Look at the windshield. If it has been wet and suddenly gets drier, this may be because it has turned colder outside, and the road has frozen.
  • Open farmland. Wind blowing across the fields can dump snow on the roadway and polish it smooth.
  • Watch when the rain freezes on the windshield and no longer splashes of the tires on the cars in front. The rain will freeze to ice on contact with the road
  • Shady forest areas. Here, the night-time cold can hang around and moisture can turn to ice.

Drive carfully – and stay observant

Never mess with safety! Especially when there is risk of black ice, dropping attention when driving may have very unpleasant consequences.

If you want more tips on how you can improve your performance on icy roads, download  5 ways to improve performance in slippery conditions.

5 ways to improve performance in slippery conditions

Rescue Driving Commercial Driver

Boel Haglund

About Boel Haglund

Boel was previously Digital Marketing Manager at VBG Group Truck Equipment, in Vänersborg, Sweden. She has over ten years of experience in the field, and received an MBA from University of Gothenburg, School of Business, Economics and Law. When she is not crafting different digital media strategies you can find her busy cheering in the stands of Gothenburg Cheer One, renovating the garden and finding new material for her autobiography.
Boel était auparavant responsable du marketing digital chez VBG Group Truck Equipment, à Vänersborg, en Suède. Elle a plus de dix ans d'expérience dans le domaine et a obtenu un MBA de la School of Business, Economics and Law de l'Université de Göteborg. Lorsqu'elle n'élabore pas différentes stratégies en matière de médias numériques, vous pouvez la trouver acclamée dans les stands de Gothenburg Cheer One, rénover son jardin et trouver de nouveaux éléments pour son autobiographie.


Subscribe to blog updates

Recent Posts

Posts by Topic

see all

Follow us