Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Binghamton New York
638 am EST Friday Nov 28 2014
a westerly flow of cold air will develop lake effect snow
today...with the heaviest accumulation over the northern Finger
Lakes into the western Mohawk Valley. Elsewhere...just some
scattered snow showers are expected. A warm front approaching the
area from the Ohio Valley will bring additional snow showers on
Near term /until 6 PM this evening/...
shrp upper WV over western New York at this time moving slowly east. Some light lake
enhanced snow showers along and ahead of the upper trough moving into the forecast
area at this time. As the WV pulls out...a well aligned westerly flow develops
averaging around 280 degrees. With rsnbl instability off the lake
and a fairly hi inversion...single band le event is expeceted to develop off
Ontario into the northern zones. Mvmt of the upper WV has been a bit
slower than expeceted so the band has not yet developed...but this in turn
shd allow it to linger longer into the evening before drier
air...lowered inversion...and strengthening ll shear weakens the band. Have
gone ahead and extended the advisory through 00z to cover the expeceted band timing.
Snowfall amts have been edged up a bit...and of course extended into
the evening. Total amts not all that much more since the onset is
delayed...and band shd continue to drift north...especially near the end of
the advisory period.
Short term /6 PM this evening through Sunday night/...
several factors bring an end to the le band in the forecast area
including shear...drier air...and a more southwesterly flow developing ahead of
the next WV. Overnight hours shd gnrly be dry other than the chance of a
bit of Erie le and weak overrunning precipitation into Sat morning.
Gnrly overcast Sat as the warm air advection continues and still the chance of some light
precipitation...especially over the northern and western zones with stronger uvm and some
lake moisture available. Gnrl west-southwest flow with pockets of middle level moisture
and lift Sat night into sun. This will lead to overcast skies and perhaps
some light precipitation. Temperatures on sun hi enough for for any precipitation to be liquid.
Temperatures sun will rise to to above normal...but guidance may not be fully
accounting for the snow cover...especially over the eastern zones so have gone
slightly cooler in the grids.
Long term /Monday through Thursday/...
345 am update...
00z GFS is still the fastest with frontal passage early in the long term.
Latest GFS suggests cold front will be located along eastern Seaboard by 12z
Monday while ec has fnt bisecting County Warning Area with CMC still back to the
west. Have made no changes to Monday forecast as models continue to diverge
on speed of frontal passage. Northwest flow following front will likely bring lake effect
snows to favored regions Monday night before 1040mb high builds over County Warning Area on
Expect Tuesday to be the coldest day of the week with highs not
expected to climb much above frzg, some 10 degrees below normal. Next
system looks to mv in late Tuesday night with cold front expected to mv through
on Wednesday. Srly flow ahead of front will lead to rain/snow mix drg the
As is typical in these cases lake effect snow will follow frontal passage for
Wednesday night. Model discrepancy continues late in extended due to upper level
pattern with ec more amplified than GFS. Have made no changes to end of
the week because of uncertainty.
Aviation /12z Friday through Tuesday/...
a band of snow is moving through central terminals at this time
with MVFR/IFR restrictions. Expect IFR snow at rme by 14z while
all other locations become VFR after this time. May see MVFR
restrictions hang on at rme through 02z Saturday as west-northwest flow will
continue off of Lake Ontario.
Next round of snow looks to move in from the west after 12z
Saturday and only indicate lowering VFR ceilings after 05z.
Winds out of the west-northwest 5-10 kts will become southwesterly toward 00z.
Sat...possible restrictions from scattered -shsn.
Sun...restrictions possible from -shra.
Monday...restrictions possible from -shra/shsn.
New York...Lake effect Snow Advisory until 8 PM EST this evening for