shocked our resident chemist did not post the possibility of snow showers across portions of our area tonight into the morning as a very weak clipper system heads our way
Clipper system looks
likely to degenerate at the surface as it
heads southeastward and redevelop along the Carolina coast as
the
upper level trough closes off for a time as it heads towards
the southeastern coast. The bulk of the forcing and
moisture
associated with that system will stay well to our southwest.
However, the
moisture moving west off the ocean looks like it
will be just enough when coupled with some
isentropic lift aloft
and
vorticity advection on the north side of the system to bring
some of those
scattered showers over the ocean inland.
QPF looks
minimal to negligible for most of the region, and temperatures
will be moderating as the easterly
flow brings a relatively
warmer
air mass inland, so while it may start as flurries/snow
showers nearly everywhere, think a transition to sprinkles/rain
showers will occur as we
head through tonight and Wednesday
morning starting near the coast and heading inland. Highest
coverage of precipitation looks to be late tonight based on best
isentropic lift and upper-level
PVA, which is still a bit tricky
in the Delaware Valley, but should be mostly rain southeast of
I-95 while snow across the LV and Poconos into NW NJ. Have
confined any snow accumulations to these latter areas but still
expect no more than an inch accumulation, mainly in the high
Poconos. Near and southeast of I-95 not expecting any impacts,
but in the Lehigh Valley and NW NJ, minor accumulations are
possible on paved surfaces overnight tonight which could result
in slippery roads, with better odds of this occurring in the
higher terrain of the Poconos. Temperatures will be fairly
steady through tonight.
System starts pulling away with weakening forcing on Wednesday,
so temps should moderate a bit more as precip mostly dwindles.
Maintain some sprinkles/flurries thru the day however given some
CAMS like the 12Z HRRR are indicative of such. Highs should turn
out milder with the oceanic
flow continuing, nudging into the
lower 40s along and east of I-95, but 30s further NW.