759
FXUS61 KBGM 191404
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
904 AM EST Sun Jan 19 2025

.SYNOPSIS...
A quick moving coastal low pressure system will result in
several inches of snow for parts of the area this afternoon
into the evening, especially for the Poconos and Catskills. Very
cold arctic air will settle into the region Monday through at
least Wednesday with temperatures in the single digits and teens
for highs and lows below 0. Wind chills will likely be below 0
for much of the first half of the week.

&&

.NEAR TERM /THROUGH MONDAY/...

900 AM Update...

System is moving in earlier than anticipated, therefore adjusted
pops higher for this update. Also used a blend of the NBM QPF
with the official forecast to bump up amounts. Otherwise made
the usual changed to temperatures and dewpoints using current
observations. Remaining forecast is on track at this time.

630 AM update...

No changes made to the previous forecast.

300 AM update...

A neutrally to slightly positively tilted trough is digging
into the Central US early this morning with the first hints of a
baroclinic leaf on water vapor imagery over the SE US. A
surface low will eventually form over the next few hours and
propagate quickly into the NE US along the cold front. The low
will deepen as it moves up the coast with the 500 mb trough
trying to become more negatively tilted by mid afternoon. With a
jet max at 250 mb moving into the Carolinas today, there will
be some upper level divergence over eastern PA up through
eastern NY helping to enhance lift as the low moves closer. The
850 and 700 mb frontogenesis has been consistent in placement in
NEPA through southern Catskills and Hudson Valley of NY. Snow
ratios were increased to around 20:1 under this band to help
increase the snow totals this afternoon. Overall QPF with this
storm is on the lower end due to the quick forward speed of the
low but a 1 to 3 hour window of 1+ inch snowfall rates is likely
under the snow band that develops.

Cross sections from the Atlantic Coast through to the Great
Lakes do show that the frontogenesis continues up through 500 mb
though dry air advecting into the low at the surface will
greatly limit the westward extent of the snow. I-88 really looks
to be the cut off with areas NW of the interstate will likely
not see much snow out of this system. The Poconos may do pretty
well with the NW winds and decent low level moisture may lead to
some topographical enhancement where ridges may approach 8 to
10 inches of accumulation this afternoon.

As the low departs Sunday night, an arctic front moves in with
temperatures falling into the single digits with wind so wind
chills will likely be well below 0. With little ice cover on the
Great Lakes still, lake effect snow develops off of Ontario
though with the cold dry air and the dendritic growth zone
basically at the surface, the inland extend of the snow may be
limited. Heaviest snow will be closer to the Lake and likely not
extend much into Onondaga or Cayuga counties Sunday night.

Monday looks cold with highs struggling to make it into the
teens for most of the area with breezy conditions persisting.
Wind chills are looking to stay at or below 0 for most of the
day. With a little bit of day time heating with breaks of sun
between lake effect clouds, the lake effect off of both Ontartio
and Erie will be able to extend farther inland so chances of
precipitation were increased for the Southern Tier and
northward. Snow amounts with these bands that extend into our
forecast area will likely be only a few tenths of an inch.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
305 AM Update...

Broad cyclonic flow amplifies over the eastern one-third of the
Nation which ushers in the long advertised cold snap. Surface high
pressure ducks in south of the Eastern Great Lakes which will be the
core of the cold air. Hazardous cold peaks late Monday night and
again late Tuesday night with overnight lows near and below zero
along with very sub-zero apparent temperatures from wind chill.
There will only be nominal recovery during the daytime each day with
highs in the single digits and teens. With the high cresting mainly
south of our area, the boundary layer flow appears to be setting up
along W-SW trajectories which would keep significant LES out of CNY.
Ontario lake bands may clip N. Oneida for a bit on Monday night and
Erie band snow showers could bring a few inches in spots across the
Finger Lakes region, but nothing to get too excited over in the dead
of winter as far as headlines go. Will address any cold
temperature headlines once we have cleared the imminent snow
event out of the area.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
305 AM Update...

We remain within the broad Eastern meridional trough through the
rest of the week, but are expected to see temperatures moderate back
toward seasonal normals as south to southwesterly flow opens up with
high pressure retreating into the Atlantic. A continued west-
southwest low level flow, the lake effect machines are expected to
keep pointing north of CNY and NEPA. Given the expected high
amplitude in the pattern, the energy rotating around the longwave
trough is being indicated by model consensus to stay south of the
Northeast indicating a relatively quiet week coming up for most of
our area. This idea has good confidence until perhaps Friday or
Saturday when the spread of solutions opens up to suggest a coastal
system clipping our NEPA/SENY counties comes back within the
envelope of possibility. Confidence is quite low regarding late next
week/early weekend, but still noteworthy enough to monitor for
westward model trends.

A sub-zero start to the whole week gets back at least into the 20s
and maybe some low 30s by this time next weekend.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
MVFR cigs persist at all terminals early this morning. Light
snow moves in today with NEPA seeing most of the snow. AVP will
have the best chance at heavier snow with IFR or LIFR vis from
around 18Z through 0Z before a slow improvement towards 6Z. SYR
and RME may miss out on the snow associated with the coastal low
but some lake effect snow develops towards 6Z as the low
departs that may cause some MVFR or IFR restrictions. Cold dry
air moving in tonight may help clear out cigs with better
chances of VFR after 6Z tonight at all terminals.

Outlook...

Monday through Wednesday...Lake effect snow showers and
associated restrictions possible, especially for KSYR-KRME.

Thursday...Mainly VFR.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory until 1 AM EST Monday for PAZ039-043.
     Winter Storm Warning until 1 AM EST Monday for PAZ040-044-047-
     048-072.
NY...Winter Weather Advisory until 1 AM EST Monday for NYZ057.
     Winter Storm Warning until 1 AM EST Monday for NYZ062.

&&

$$

SYNOPSIS...AJG/BJG
NEAR TERM...AJG/ES
SHORT TERM...JAB
LONG TERM...JAB
AVIATION...AJG/JTC