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fxus61 kbgm 251846 
afdbgm

Area forecast discussion
National Weather Service Binghamton New York
246 PM EDT Sat Mar 25 2017

Synopsis...
periodic light rain will continue over the next few days, as
moisture and several upper air disturbances overrun a nearby frontal
zone. For the most part, seasonably chilly conditions will
prevail this weekend, with temperatures mainly in the thirties
and forties. Milder air should push in on Monday, with highs
back into the fifties.

&&

Near term /until 6 PM this evening/...
updated at 10 am... made some adjustments to the short term
forecast based on latest observed trends. The surface front is
located over southern Luzerne County this morning with the
latest temperature at Hazelton up to 61 while avp is at 46 and
most of New York state is in the 30s. There have been scattered light
showers over the Poconos along the surface front. Most of the
rain this morning is across our northern counties along a deeper
boundary extending from the southern edge of Lake Ontario east
toward the mid-upper Hudson Valley. Steady rain is falling at
Syracuse and Rome with temperatures in the mid 30s. We are
watching for any icing in that area with temperatures so close
to freezing but so far it looks like temperatures are just warm
enough to keep this precipitation liquid. Between these two
areas of rain over the twin tiers of New York/PA skies are cloudy with
areas of fog and spotty drizzle but no significant rain
occurring this morning. Expect the surface front to sag south of
Hazelton later today with temperatures falling to the 40s...
and expect the rain over our northern counties to work slowly
southward per latest high resolution guidance. Latest forecast
update reflects these trends. Previous discussion is below.



4 am update... a tight low-level thermal gradient exists across
the forecast area this morning (30s in cny and upper 40s-mid 50s
in nepa), owing to a west-east frontal zone draped along the PA/New York
border. In the meantime, areas of light rain are also
traversing cny, near and to the north of the aforementioned
front.

For today, the surface front should continue to push southward,
as a large eastern Canadian high pressure ridge builds towards
the southeast. As a result, colder air north of the boundary
will build over the forecast area. This will keep readings
mainly in the 30s to near 40 over cny, with late morning highs
in the 50s across parts of nepa, before temperatures start to
fall during the afternoon.

As for precipitation, light rain will continue through the
midday hours, mainly over cny, as mid-level thermal advection
forcing continues. The forced ascent should weaken for a time by
later today, as somewhat drier air also attempts to build
southward from Ontario/Quebec, resulting in a diminishing trend
for rainfall through the afternoon.

&&

Short term /6 PM this evening through Monday/...
415 am update... by tonight, the surface front is expected to
have pushed well southward towards the Delmarva region. Weak
forcing and shallow moisture will remain in place over cny/nepa,
resulting in lots of lower clouds, along with patchy light
rain/drizzle. Surface temperatures may drop to near or just
below 32f over northern and eastern parts of the forecast area
(mostly the southern Tug Hill, Mohawk Valley, and Catskill
regions), with spotty freezing drizzle possible.

Sunday, more of the same, with patchy light rain/drizzle,
especially in the morning. Afternoon highs should range from the
30s in the Catskills and Poconos to the mid 40s over The Finger
lakes region.

Sunday night-Monday, a large-scale upper trough should approach
the region from the west, as the mid-Atlantic surface front
begins to move back northward as a warm front. Thus, forced lift
should improve again over cny/nepa, with rain becoming more
widespread, especially later Sunday night into Monday. As for
temperatures, although they may remain marginally cold enough
for spotty light freezing rain in the Catskills late Sunday
night into Monday, they should be warming with time overall, as
the cold wedge north of the front begins to erode from the
south and west.

&&

Long term /Monday night through Friday/...
300 am EDT update...
the start of the extended forecast will be an active one as multiple
shortwaves are forecast to move across the region. Made minor
adjustments to the previous forecast. High pressure is expected to
move into the region on Wednesday and provide a break to the wet
pattern we are having. The next storm system to impact the region
will move start to move into the region early Friday morning and may
create showers through the weekend.

Temps during the forecast period will be at or slightly above the
seasonal norm.

&&

Aviation /19z Saturday through Thursday/...
conditions will be improving across the northern taf sites late
this afternoon through this evening, while conditions
deteriorate at avp and remain in the IFR or low MVFR range at
bgm and Elm. Dryer air moving in from the north will allow for
MVFR and occasional VFR conditions to develop at rme and syr
this evening. Moisture will return across those areas late
tonight with MVFR conditions developing along with possibly some
light freezing rain. Meanwhile, IFR conditions over southern New York
will spread slowly south late today with MVFR conditions
showing up at avp late this afternoon or early this evening then
continuing through tonight. Most places will have MVFR
conditions during the day Sunday.

Winds will be from the north-northeast late today into this
evening at less than 10 kts shifting to southeast at 5 to 10 kts
late tonight and Sunday.

Outlook...

Sunday night through Tuesday...restrictions likely from waves
of rain as frontal boundary waffles over the area.

Wednesday...mainly VFR.

&&

Hydrology...
new - 245 PM EDT...a rain on snow melt situation is underway
this weekend, and is expected to increase early next week as
temperatures in the 50s-60s become more widespread across the
region. This warmth will also be accompanied by an increase in
surface dewpoints into the 40s.

Model averaged quantitative precipitation forecast suggests roughly an inch of precipitation
across the area through Monday night. This alone would not be
enough to trigger any flood worries, however, the almost 2.5" of
liquid water content across the headwaters of the upper
Susquehanna, Delaware and the Oneida-Syracuse river basins does
get our attention. After melting, and rainfall contribution, the
operational hydrologic model simulations are getting a few
areas of the upper Susquehanna and her tributaries to minor
flood stage by the middle of next week. Mmefs ensemble spreads
do also suggest potential for widespread minor flooding and
some chance to reach moderate at a few forecast points. There
remains considerable uncertainty, and time, to not raise any
public flags at this point, however, we have started core
partner decision support for early-look resource and risk
management planning efforts.

&&

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

&&

$$
Synopsis...mlj

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