PITTSBURGH—A blast of icy weather brought winter back across Pennsylvania on Tuesday, but it may be just a little less cold in a few days.

The freezing temperatures caused icy roads across much of the state, which had been experiencing milder temperatures.

"It's an old-fashioned cold winter day. It's nothing record breaking, but definitely well below normal," said Rodeny Smith, a meteorologist with the National Weather Service in Pittsburgh. Temperatures could drop to zero or even 5 below for much of Pennsylvania Tuesday night and on Wednesday morning, and wind chills will make that feel like 10 or 20 below zero. Some areas could get 4 to 8 inches of snow, too.

Temperatures in Philadelphia won't be so low—about 14 degrees Tuesday night.

Many school systems in western Pennsylvania delayed opening by two hours on Tuesday morning.

In northwestern Pennsylvania, a portion of Interstate 90 had to be closed Monday night because of a snowstorm that blanketed that region.