By Carol Erickson

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PHILADELPHIA (CBS) — A vigorous storm system has blanketed the Philadelphia area with inches of snow from an especially heavy and long lasting band of precipitation.

The following counties are now in a Winter Storm Warning area until midnight: Philadelphia, New Castle, Salem, Gloucester, Burlington, and Delaware.

3 to 6 inches of snow could fall in these areas until a gradual changeover to rain overnight. Areas to the north through the Lehigh Valley and Poconos are covered by a Winter Weather Advisory until the overnight time period for a slower change to rain.

Travel is extremely dangerous, with even treated roads becoming slippery.

READ MORE: Philadelphia Weather: Fast Storm System To Bring Snow To Parts Of Delaware Valley Sunday Evening

Warmer air has started to move north from the shore areas inland, but at this point not warm enough for a change to rain in any location.

Periods of sleet are expected until rain arrives to the south; the snow in the Philadelphia area will change to sleet before changing to rain. The possibility of freezing rain for a brief time also exists.

By Monday, all areas will still be wet, but this time with rain as temperatures climb into the middle 40’s.

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