GOTTA SCALE DOWN THIS STORM FORECAST

Yet another forecast snow bites the dust.   The 1 AM runs of the GFS and NAM show the low pressure development Saturday night to be very unimpressive.   The track is further south, the intensification is less and the precipitation rate is lower.  Surface temperatures appear warmer.

With the current trends, I’m significantly scaling down the snow forecast.

In the immediate PHL area and immediate suburbs, little accumulation is expected on roads and paved surfaces and perhaps a wet coating on grassy surfaces.   It looks to be principally rain mixed with some wet snow here in PHL and the immediate suburbs.

Things may change again.  I’ll update this evening.

10 AM Friday Update- Latest NAM again has 0.60 inches QPF , starting about 6 PM.   Temperatures in Philadelphia appear just on the borderline too warm for snow at the start, but my concern about dynamic cooling might come into play here again. So I may have to backtrack to last night’s forecast  with a few inches of snow, mostly on grassy surfaces in the PHL immediate area!

Sorry for the flips back and forth on the forecast, but this forecast is plagued with boundary conditions that could go either way.   That said, this morning’s NAM was looking colder than its previous run.  We won’t know until tonight at the earliest, and it may need to wait until Saturday morning for the final handle on things.