With more winter weather in the forecast for this week, New Jersey drivers and state transportation officials are hoping we don't see a repeat of what happened two days ago, when many roads suddenly became covered with a thin layer of black ice, causing hundreds of accidents.

Ice covers a roadway. (Moses Robinson, Getty Images News)

That kind of storm is dangerous and challenging, it's the most challenging and difficult," said NJ Department of Transportation Spokesman Steve Schapiro.

Schapiro said crews did not pre-treat roadways with brine or salt because it would have  simply washed away when the rain started, but it had been very cold for several days and "surface temperatures were near freezing and in some cases below freezing, so when the precipitation began basically what happened was you had a flash freeze."

He said what the DOT will do is follow the progress of the storm very closely, activate crews before any precipitation is expected to fall, and then "get them out there in their trucks ready to go."

"As soon as that precipitation starts, they get out there, treating as aggressively and effectively as possible," he said. "But it's very challenging because you're talking about thousands of miles of roadway, ramps, bridges and sometimes mother nature will get the upper hand for a while - it's the most challenging type of storm we have."

Schapiro said black ice is when a layer of ice that forms on the road, so the road can become like a skating rink, and it is a very dangerous situation.

"It's hard to see so a lot of times drivers might not realize how slippery the roads may be," he said.

He added another important factor is "having that partnership with the motorist out there, having them understand that it's very important to reduce your speed, to leave plenty of distance between you and the vehicle in front of you."

"Be patient and plan for extra travel time - and stay back from salting and plowing crews to let them do their work," Schapiro said.

The bottom line, he said, is during the winter, road conditions can change very quickly.

"You may be driving on a road and everything is fine," he said. "But just up a little ways the conditions may get treacherous, so slow down and take it easy."