Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Binghamton New York
issued by National Weather Service State College PA
205 PM EST Monday Nov 30 2015
high pressure ridging southwest from the New England states will
bring a sunny and pleasant day to much of our region today...before
a storm system spreads thickening cloud cover...then rain
northward into PA and New York for early Tuesday through Wednesday
Near term /until 6 PM this evening/...
Sunny skies prevail across most of the County Warning Area early this afternoon.
Developing 925 mb southeasterly flow tapping moisture from the western Atlantic
has spread a deck of strato cumulus north into the Endless Mountains
of nepa and toward the Chemung Valley of southern New York.
The lower cloud deck will reach the Penn/New York border in vicinity of kbgm around
or shortly after dusk....while locations across the northern Poconos and
eastern ginger lakes region sees clouds encroach from the SW and southeast
later this evening.
The few-several hours of clear skies early this evening could pose
later problems for a potential light freezing rain event late
tonight/early Tuesday over the northern Poconos and southern Catskills.
Temperatures for the rest of the afternoon will be nearly
steady in the upper 30s to middle 40s.
Short term /6 PM this evening through Tuesday night/...
thickening...layered clouds will advance north across southern New
York this evening. Areas of clearing this evening across the southern
Catskills and northern Poconos will allow for enhanced radiational
cooling and a higher probability of sub-freezing surface temperatures as light rain
moves in from the south late tonight through early Tuesday. Storm Prediction Center sseo
shows a chance for -fzra for several hours early Tuesday...but after
collab with okx...decided that confidence in the location and chance
for -fzra was low enough to hold off on an advisory at this point in
Any freezing rain will likely be limited to the eastern edge of
the precipitation and is not expected to last long, as warm air advection in rain should
soon scour out the cold air.
Focus on high res model precipitation type and Storm Prediction Center/S sseo late this
afternoon and early tonight will help to better clarify location and
timing of any -frza threat.
Confidence for rain later tonight...Tuesday and Wednesday is near
100 percent. However...confidence regarding the exact onset is
After the front passes on Wednesday, rain will taper off to showers.
Total quantitative precipitation forecast will be around 0.75 to 1.00 inches.
As cold air pours in for Wednesday night, rain showers will mix
with snow showers, with little or no accumulation expected.
Long term /Wednesday through Sunday/...
4 am update...no significant changes needed to extended forecast
as models remain consistent with previous cycle. Thursday will
feature mixed snow/rain showers across much of central New York
but especially southeast of Lake Ontario where some lake enhanced
activity is likely. Here minor snow accums may occur early
Thursday morning but in general less than an inch. Rest of the
period will be fair as an upper level ridge will reside over the
northeast along with a large area of high pressure at the surface.
in the big picture, no major changes to the overall weather
pattern as an overall progressive / low amplitude upper level
flow remains in place. What this means is temperatures generally
continuing around or above average with no major Arctic outbreaks
or winter storms on the horizon. Forecast models are in good
agreement on this big picture so forecast confidence fairly high.
For the gridded forecast itself, utilized model blend procedure,
known as the superblend, with only very minor adjustments made.
For daily sensible weather, cooler conditions move back in Wednesday
night into Thursday on the back side of departing system with
lingering rain/snow showers, mainly for central NY, due to lake
effect. Ridging briefly takes hold late Thursday into early Friday
before a weak system brings the chance of a few showers by late
Friday over northern zones. Highs both Thursday and Friday will be
around seasonal...generally in the low to middle 40s.
Early indications are for high pressure to dominate next weekend
with sunshine and moderating temperatures.
Aviation /15z Monday through Friday/...
surface high pressure ridging southwestward from New England will maintain VFR
for much of the region through the rest of the daylight hours
today. The exception will be across nepa /kavp/ where a broken-overcast
deck of MVFR strato cumulus will spread north across the airfield
during the middle to late afternoon hours.
Overnight, surface low pressure in the middle Atlantic and upper Great Lakes
will provide a moist southeast flow. At krme/ksyr, ceilings will remain VFR
but lower to around 4k feet toward the end of the taf period. Across
the southern terminals a moist southeast flow will bring a marine layer
with low MVFR ceilings most likely developing between 03z-06z.
Conditions could fall to high end MVFR as early as 01z at these
southern New York state terminals. At kavp...light rain will begin around
06z and around 09z at kbgm/kelm.
Light east/southeast winds around 5 knots through early tonight. Included low level wind shear
late tonight into Tuesday for all taf sites...with slighter later
timing across central New York.
Tue-Wed...restrictions are likely, in lower ceilings and light
rain. Low level wind shear Tuesday.
Thu/Fri...mostly VFR, but brief restrictions possible in rain or
snow showers...mainly for central New York.