BOSTON (AP) -- Forecasters from Philadelphia to Portland, Maine, have warned that "flash freezing" could make roads dangerously slippery a day after snow fell on much of the East Coast.

 

National Weather Service forecaster Bill Simpson in Massachusetts said Monday night the biggest concern was for areas where rain and slush ponded on roads before temperatures plunged. "They are going to have a pretty difficult time when that slush freezes," he said.

Arctic temperatures following the storm were expected to bring minus 20 degree wind chills in parts of Pennsylvania, New York and New England, and minus 35 degrees in pockets near the Canadian border.