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Area forecast discussion 
National Weather Service Binghamton New York
1258 am EST Monday Nov 24 2014

Synopsis...
rain will overspread the area tonight...as a warm front pushes
through from south to north. Monday will be unseasonably
mild...with a few hit and miss showers...and temperatures in the
60s. A cold front will progress through the region Monday
night...with chillier and more seasonable temperatures settling in
thereafter.

&&

Near term /until 6 am this morning/...
910 PM update...
slowed down the timing of the rain tonight, more in line with
current radar trends and hrrr. Otherwise everything looks good.
Previous afd is below.

315 PM update... residual light showers/sprinkles will lift out of the
region by 21-23z...with some clearing pushing in from PA for the late
afternoon/early evening hours.

This will be short-lived...though...as a warm frontal boundary and area of
steady rainfall are northbound from the southeastern/mid-Atlantic states.
We expect rain to overspread the forecast area from S to north...generally in the
02-06z period. Although forced ascent is fairly strong overnight...the
overall system is fast moving...and thus maximum rainfall amts should be
kept mostly in the 0.50.75" range...mainly from about I-81 eastward.

Strong srly flow and low-level warm air advection will result in a non-diurnal temperature
trend once again...with rising temperatures foreseen after 06z.

&&

Short term /6 am this morning through Tuesday night/...
325 PM update... we still expect that cny/NE PA will break into
the warm sector Monday...setting the stage for high temperatures that could
approach record values in some places (well into the 60s).
Although a good chunk of the day is likely to be rain-free
isolated-scattered showers can't be ruled out...given a fairly moist
air mass...and the approach of a surface cold front late in the day.

The just referred to cold front should progress eastward through the
County Warning Area Monday evening...accompanied by scattered showers. A cold air advection regime will then be
with US from late Monday night...through Tuesday...and Tuesday night.

Although colder air will gradually work its way back into cny/NE
PA this period...the optimum word is gradual...as the main chunk of
Arctic air at least initially hangs back in the upper Midwest and
southern Canada. Also...the prevailing flow will be southwesterly this
period...steering any les (which should not be sig anyway...given much
less lake generated instability...and lower inversion heights than what we
saw last week) mainly to the north and west of our forecast area. In
fact...at least through the day Tuesday...blyr temperatures continue to look
as though they could support a -shra/-shsn mix.

By later Tuesday night...any lingering light -shsn/flurries should be on the
wane...as the flow weakens...and low-level moisture dries up. We'll
then turn our eyes to the S...to see what happens with potential
coastal cyclogenesis towards the upcoming Holiday period. More on this
below.

&&

Long term /Wednesday through Sunday/...
the focus of the extended period is on the potential coastal storm
Wednesday into Wednesday night during one of the highest peak
travel times of the year.

Models continue to waver on the cyclone position, though the European model (ecmwf)
is the most stable solution. Taking a consensus GFS-European model (ecmwf) forecast
into account, light amounts of snow would fall from just west of
the I-81 corridor back toward the Wyoming Valley. Two to five
inches of snow would fall within a corridor from the Poconos up
through the Catskills where we have raised probability of precipitation to likely.

Will continue to monitor the models and the observed development
of this system. The trend however is for probability of precipitation and snowfall to
increase.

The remainder of the long term period...used HPC guidance with
mesoscale adjustments for potential lake snow areas. Trough will
descend upon the northestern Continental U.S. Once again with a persistent polar
flow out of Canada. Both Lake Erie and Lake Ontario will activate,
but it is too early to determine where the bands will line up
exactly. Best first guess: accumulations are most likely from far
northern Onondaga County into northern and western Oneida County.

&&

Aviation /06z Monday through Friday/...
most significant part of this forecast will be the low level wind
shear that will impact the region through late afternoon due to a
strong low level jet of approximately 50 knots about 2k feet off the
surface. A band of mainly light rain will lift through the
terminals generally between 06z-12z. In general low MVFR ceilings are
expected with this except occasional IFR at ktih between 08z-12z,
at kbgm between 08z-15z and at kavp between 11z-15z. Conditions
will gradually improve to VFR middle/late morning as region resides
in warm sector. This evening the surface occlusion will move through
but boundary is fairly dry with no prolonged restrictions
expected.

Southeast surface winds between 8-12kts with gusts to 25 knots in the
higher terrain shifting to southerly by middle morning at 10-15 knots
with gusts near 25kts. Winds becoming southwest this evening at
12-15 knots with gusts around 25 knots.

Outlook...

Tuesday-Tuesday night...mainly VFR.

Wednesday-Wednesday night...coastal system may impact region with restrictions from
snow...best chance kavp.

Thu/Fri...possible restrictions from scattered -shsn...especially ksyr-krme.

&&

Bgm watches/warnings/advisories...
PA...none.
New York...none.

&&

$$
Synopsis...mlj
near term...heden/mlj
short term...mlj
long term...djp
aviation...rrm

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