PHILADELPHIA (CBS) — A slow-moving storm system will continue to move through the region today and tonight.  Expect on and off light rain and snow showers through the day, with the best chance to see some snow north of Philly.

Temperatures will be above freezing so little or no accumulation expected during the day.  Temperatures in the Poconos will remain at or below freezing with an inch or two of snow accumulation possible by Sunday morning.

A winter weather advisory is in effect until early Sunday morning for Berks, Lehigh Valley and the Poconos.  As the storm passes offshore and intensifies later tonight, colder air will return. Rain showers will change to snow showers late tonight, even as far south as Philly.  Overnight, a coating of snow is possible, mainly north of Philly on untreated surfaces.

Improving conditions then return for the 2nd half of the weekend.  A few snow showers are possible early on Sunday morning, then sunshine returns with temperatures remaining below average in the 40s.  Astronomical Spring officially arrives on Monday with highs about 5 degrees below average near 50 degree.  The overall pattern for the first week of Spring continues with high temperatures near or below average.