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Area forecast discussion 
National Weather Service Binghamton New York
929 PM EDT Tuesday Oct 21 2014

Synopsis...
a large upper low over western Pennsylvania this afternoon will
drift southeast to near the coast of Maryland tomorrow
evening...then near Maine on Friday. This will keep clouds...cool
air... and periods of rain in the area for the rest of the work
week.

&&

Near term /through Wednesday/...
little movement of the upper low and synoptic low this shift.
Showers are lining up as forecast over the southeastern fa, with lesser
probability of precipitation to the northwest farther away from the cyclone.

Updated the near term T/dew point grids and the probability of precipitation to better fit
current scenario and short term mesoscale runs.

4 PM update...
swirl clearly vsbl in the radar mosaic over western PA Marks the center
of the upper low. NAM forecast a nearly due south mvmt overnight bring the
center over eastern Virginia by 12z Wednesday. Surface low is not yet well developed...so
upper low deepens slowly. This in turn limits the Ely inflow.
So...while there/S plenty of moisture around...limted instability
and a more southerly than Ely flow shd limit the precipitation overnight...as it has
so far today.

Expect continued light showers and drizzle at times overnight...and only a
limited diurnal swing in temperatures.

&&

Short term /Wednesday night through Friday/...
blocky pattern continues with the closed low slowly deepening and drifting
newrd off the Atlantic CST. Wednesday actually looks fairly dry as the
developing Ely flow has not yet pulled the deeper moisture and
instability back to the west and into the forecast area. As the low
continues to deepen...persistant flow will eventually bring higher
probability of precipitation and quantitative precipitation forecast to the area. At this time looks like the best chance for
heavier rain may actually hold off until late Thursday into early Friday as
the low kind of bottoms out near Cape Cod.

Later Friday...blocking ridge to the north fnly begins to mve out
allowing the low to accelerate to the NE. This could allow some
drier air to work into the western and southern zones late in the period.

Temperatures through the period will gnrly be a bit below normal during the
day...but milder at night. This may allow temperatures on average to even be
slightly above normal.

&&

Long term /Friday night through Tuesday/...
2 PM update...
500 mb low will be spinning off of the Cape Cod coast at the start of
the extended. This will keep light precipitation in across the area before slowly
winding down by the end of the week. Next system will appch the northern
zones Sat into Sat night with perhaps an isolated shower. After this WV
mvs east, hipres builds in late in the weekend.

Temperatures expected to moderate after closed low ejects into the Canadian
Maritimes Friday night. For the weekend expect highs to be above normal
values as high builds in.

&&

Aviation /02z Wednesday through Sunday/...
a cutoff low over the middle Atlantic region will gradually lift
northeast during the next couple of days and keep the weather
unsettled. At krme/ksyr, north/NE low level flow overnight will keep
ceilings generally in the MVFR/low VFR category due to down sloping. On
Wednesday winds will shift to the northwest with MVFR ceilings
becoming more common. At kith/kbgm/kelm, north/northwest flow will generally
lead to MVFR/low MVFR ceilings. Due to model soundings indicating
significant low level saturation along with favorable wind
direction, IFR ceilings will be possible between 09z-13z. On Wednesday,
ceilings will remain primarily low MVFR. At kavp, ceilings are expected to
lower into the MVFR/low MVFR category overnight and remain there
through Wednesday.

Northerly winds around 5 knots becoming northwest by middle morning
Wednesday around 10 knots.

Outlook...

Wednesday night through Friday...widespread restrictions in lower
cigs/-shra. High confidence of MVFR...low-moderate confidence in
IFR at times.

Sat...becoming VFR though potential exists for MVFR across
northern terminals.

Sunday...VFR.

&&

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

&&

$$
Synopsis...dgm
near term...dgm/djp
short term...dgm
long term...pvf
aviation...rrm

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