Another round of rain from another southern system forthcoming tomorrow night. This storm system will bring rain to the vast majority of the Delaware Valley. However, farther north could see a period of icy rain, sleet, or snow at the onset of the storm and for at least a portion. Most computer guidance except the GFS model shows at least some frozen/freezing precipitation in the Poconos and the higher elevations of the Lehigh Valley tomorrow evening. Precipitation moves into the Philadelphia region around 4 PM, with the Lehigh Valley in on the event around 6 PM or so. The icy rain or sleet/snow combo should transition over to rain for everyone in the Poconos but the higher elevations up there might get a couple of inches of snow or some icy surfaces for a time before temperatures moderate above freezing aloft and at the surface.
Rainfall totals should exceed an inch in most spots, with the potential for a couple of inches in the heaviest locations (NAM suggests that, with the other models solidly in the one to one and a half inch department).
After this, we will transition to colder weather late Thursday night with a second cold front coming in from the west. That front will bring more showers to the region, which may end as a shot of snow to the north/west of Philadelphia on Friday morning. Accumulations would be minor if that changeover to snow does occur...and probably most likely on the highest hills and in the Poconos.