A quick update.  Latest NAM and GFS have come closer together in QPF. The afternoon runs have 0.12 (NAM) and 0.16 (GFS) falling as snow, mostly before 7 AM Friday.   This translates into about 1-2 inches of snow, less north and west.

The tv weather people’s phrase, “mostly on grassy surfaces” doesn’t apply here.  The snow will be falling during the night time hours– insolation through the clouds won’t be a factor until after sunrise, when the snow will be essentially over.  Once the sun angle increases (behind the clouds), most snow on roadways will quickly melt, leaving any accumulations on grassy surfaces.

But those hitting the roads for an early commute will likely see some snow on untreated surfaces, since temperatures will be below freezing during the snowfall, especially north and west.

Fri 7 AM: The northernmost cutoff of the precip was sharp and here in the Chestnut Hill area, we hardly had more than a coating.  (In this scenario, “on the grassy surfaces applied”, but not for reasons I had considered- too light snowfall.). It appears that just south and east  of PHL airport, snowfall has been more significant. )