Tonight’s latest short range models (NAMHRRR amd GFS LAMPS) show the possibility of light snow showers late morning and early afternoon Sunday in PHL before the main slug of moisture arrives as rain Sunday evening.
Any snow should be light; maybe a coating at most.
(It should be noted that the major models hold off the precipitation for PHL until early evening and show nothing during the day.)
Sunday Evening Update: Just a few snow flurries this morning, but no light snow. Radar looked impressive, but it was all virga, never reaching the ground. So the major models prevailed here. No more snow in the forecast right now. The general trend seems to be cold and dry; when it gets wet, it also gets warm, as will be the case tomorrow.
The long term doesn’t show any snow for us and a white Christmas isn’t looking likely right now with a significant warmup possible around third week in December.
The arctic airmass hat has moved in will give us a cold and breezy weekend.
Saturday will be sunny with occasional clouds. High only 37.
Sunday will partly sunny early, then increasing cloudiness in the mid afternoon. High 37.
Light snow will move in late afternoon or early evening Sunday, but will change to light sleet and possibly some freezing rain before changing to all rain at night. Rain on Monday before cold air moves in again.
Next chance of snow is Wednesday; – not all models on board with this. The active cold pattern continues.
Saturday Update- The models keep the light snow to our north late Sunday afternoon. It appears that temperatures will be warm enough for rain by the time the main area of precipitation moves into the immediate PHL area.
The GFS has been quite inconsistent with the development of low pressure in the Sunday through Monday timeframe.
The latest trend is for low pressure to develop and move over the Great Lakes, keeping us in the warm sector. So while some light snow or mixed precipitation is possible at the start Sunday afternoon into evening, a changeover to all rain on Monday is likely. Little or no accumulation expected at this time.
Still unclear whether a secondary low will form off the coast on Monday with a change back to some snow towards the end of the day.
After a brief relative warmup with wet weather on Monday, another outbreak of cold air expected next week. The pattern remains cold and active.