Scientific Forecaster Discussion
fxus61 kbgm 181946
Area forecast discussion
National Weather Service Binghamton New York
issued by National Weather Service State College PA
246 PM EST Mon Nov 18 2019
a coastal storm system will bring a bit of rain, or a light wintry mix,
mainly east of Interstate 81, tonight into Tuesday. Later Tuesday and
Wednesday will turn out brisk and colder, with some light snow showers
or flurries from time to time.
Near term /through Tuesday/...
230 PM update... lower clouds continue to hang tough for areas near and
east of I-81 this afternoon, while breaks in the lower clouds have
developed across The Finger lakes. This has led to an east-west thermal gradient,
with readings generally in the 40s across The Finger lakes region, while areas
farther east in the thicker clouds have been stuck mainly in the 30s.
The main forecast concern remains late tonight into early Tuesday, as
deeper moisture and lift take a westward swing into our Catskill
and Pocono zones, tied to deepening coastal low pressure and an upper
trough lifting northeast through the region. Confidence in a period of
steady light precipitation is fairly high, but as for confidence in the
exact type of precipitation, not so much. The lowest few thousand feet
above ground level are fairly isothermal, and also it is very questionable
whether saturation reaches a sufficient depth to produce ice crystals/
snow flakes, or will we just be stuck with supercooled water droplets and
resultant light rain/freezing rain. At this time, we're leaning towards the
latter, with areas that are below 32f at the surface more likely to see
light freezing rain/freezing drizzle than light snow. Thus, we cut back
some on snowfall accumulations (now under an inch), but retained the
likelihood of a light glazing of ice. Due to potential travel concerns,
we'll hoist another Winter Weather Advisory later tonight into early
Tuesday morning for Oneida, Otsego, and Delaware counties.
For areas farther west, precipitation looks much lighter and more spotty,
with only patches of drizzle/freezing drizzle foreseen.
Tuesday, much of the light precipitation should shut off during the morning,
leading to just a cloudy day (plenty of residual low-level moisture).
Daytime highs should range from the upper 30s-mid 40s.
Short term /Tuesday night through Wednesday/...
240 PM update... a west-northwest flow, with associated low-level cold advection,
will set up for this period. Sounding profiles also continue to show quite
a bit of low-level moisture, so stratocumulus clouds should be plentiful
for much of cny/nepa, with the best chance for a few breaks in the clouds
over the southern Poconos in nepa.
Upper troughiness into early Wednesday, along with some lake generated
instability, will probably lead to scattered rain/snow showers, trending
more towards snow showers/flurries with time. Very shallow moisture should
keep intensities light. Lows Tuesday night should be within a few degrees
of 32, with highs Wednesday in the upper 30s-lower 40s.
Long term /Wednesday night through Sunday/...
1230 PM update... on the large-scale, an upper-level trough is expected to
sharpen up a bit later this week into next weekend, extending from central
Canada down into the Great Lakes region. This will lead to falling heights
aloft across New York/PA, eventually causing a return to unsettled and seasonably
As for the daily sensible weather, Thursday looks like the mildest day of
the period, with a broad SW flow ahead of an approaching cold front. As this
front nears and then crosses cny/nepa, rain showers will become likely
Thursday night into Friday. Decent cold air advection Post-frontal passage
should lead to lake enhanced rain/snow showers Friday afternoon, going
over to all snow showers/flurries Friday night into Saturday.
Later in the weekend, another fast moving cold front is expected to move
across the region, but this system looks weaker and more moisture starved
than its predecessor, so associated shower activity looks fairly light and
inconsequential from this early Vantage Point.
Aviation /19z Monday through Saturday/...
18z update... persistent low cloudiness and assorted restrictions (ifr
at kbgm, IFR to fuel alternate at kavp, and MVFR at krme) will continue
this afternoon across our eastern-most terminal sites. Farther west, the
mass of lower clouds has begun to break up, thus lengthy periods of
VFR are foreseen at ksyr, kith, and kelm through the afternoon and into
the early evening period.
Overnight, lower clouds will once again become entrenched throughout
cny/nepa, with widespread IFR-fuel alternate restrictions. Patchy drizzle
and fog appears most likely at kbgm and kavp, with temperatures perhaps
cold enough late at night for a bit of light snow at krme.
Tuesday, early morning lower clouds will slowly lift over time. However,
a return to VFR before 18z is only likely for kavp and ksyr.
Fri...restrictions likely in lower clouds and rain showers, perhaps
changing to snow showers by afternoon.
Sat...snow showers/flurries could bring restrictions, at least in the
morning, most likely to occur at ksyr and krme.
New York...Winter Weather Advisory from 9 PM this evening to 9 am EST
Tuesday for nyz009-037-046-057.