A hidden winter hazard: What is black ice and why does it lead to hazardous driving conditions?

A wintry mix is approaching Northeast Florida and Southeast Georgia, and snow is likely in Georgia, while most of Florida is set to see sleet and/or freezing rain.

As Florida and Georgia prepare for icy and frosty conditions, the Jacksonville Sheriff’s Office Sunday night alerted community members on social media that “black ice” is possible and may develop where rain hasn’t evaporated and freezing conditions exist. This could cause hazardous conditions for drivers.

Winter driving isn’t just about navigating through snow or cold temperatures; black ice poses a significant threat on the roads. Black ice is particularly dangerous because it is nearly invisible, blending seamlessly with the road surface.

This transparent glaze forms due to light freezing rain or the melting and refreezing of snow, water, or ice on surfaces, according to the United States Department of Agriculture. It often appears as a glossy patch on the road, which can be difficult to spot, especially at night.

Where and when to expect black ice

Black ice typically forms at temperatures just above freezing, often in the early morning or late evening when temperatures are lowest. It is commonly found on roads that receive little sunlight, such as those lined with trees or tunnels, and on less-traveled roads.

Bridges and overpasses are particularly susceptible to black ice due to the cooling effect of air passing both above and below these structures.

Recognizing black ice

While black ice is transparent, it can sometimes be detected in the right lighting conditions. Look for very smooth, glossy patches on the road, especially if the surrounding pavement appears dull. This visual cue can help drivers anticipate and react appropriately to black ice.

Safe driving practices on black ice

1. Stay calm: If you encounter black ice, remain calm and avoid overreacting. Do not hit the brakes or make sudden movements with the steering wheel.
2. Maintain control: Keep your steering wheel straight and lift your foot off the accelerator to slow down. Avoid using the brakes, as this can cause skidding.
3. Shift to low gear: If possible, shift into a low gear to gain more control over your vehicle.
4. Look for traction: Aim for areas with more traction, such as textured ice or snow-covered patches.
5. Handle skids carefully: If you skid, gently steer in the direction you want to go. If your vehicle has an anti-lock braking system (ABS), apply firm pressure to the brakes. Without ABS, pump the brakes gently.

Post-encounter actions

After encountering black ice, stay calm and drive slowly. Alert other drivers by flashing your lights and get off the road as soon as possible to wait for conditions to improve. Taking a break at a rest stop or pulling over safely off the road can help you recover your composure.

Preventing black ice encounters

To minimize the risk of encountering black ice, drive slowly and avoid tailgating. Keep your windshield clear and ensure your tires have adequate tread. Consider using snow tires and avoid using cruise control in icy conditions. If the weather is particularly bad, it’s best to stay home and avoid driving altogether.

Black ice is a hidden hazard that requires vigilance and careful driving. By understanding where and when it forms, recognizing its appearance, and knowing how to drive safely on it, drivers can reduce the risk of accidents and stay safe on winter roads.

Click here for more information from the United States Department of Agriculture.