MnDot Warns of Black Ice

The Minnesota Department of Transportation reports that the extreme low air temperatures and windy conditions the Northland will be experiencing for the next couple of days is causing black ice on area highways and on the interstate.

DULUTH, Minn.-The Minnesota Department of Transportation reports that the extreme low air temperatures and windy conditions the Northland will be experiencing for the next couple of days is causing black ice on area highways and on the interstate.

Black ice is an invisible hazard that catches drivers’ off-guard and frequently causes crashes, according to MnDot officials, and many crashes have already occurred on Interstate 35.

“We [MnDOT] have all of our changeable message signs lit warning motorists to slow down,” said Morrie Luke, MnDOT traffic engineer. “But some motorists are ignoring these messages and many have spun out.”

Black ice creates the appearance of a wet surface, but it is actually a thin, clear layer of ice on roads and bridges. Black ice forms when melting snow refreezes or when rain, drizzle, mist or fog freezes. It is most common at night and early morning when it is dark and temperatures are lowest.

Black ice often forms in tunnels and other shaded areas, on overpasses and bridges, and near lakes and rivers. The hazard can also form when snow temporarily melts from auto exhaust emissions or tire heat and from moisture vapors given off by industries located close to the highway.

For real-time traffic and travel information in Minnesota, visit www.511mn.org.