National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
127
FXUS61 KBGM 211447
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
947 AM EST Wed Nov 21 2018

.SYNOPSIS...
A strong arctic cold front will cross the area today, accompanied
by snow showers and a few snow squalls this afternoon. Bitterly
cold, but generally dry weather will follow for Thanksgiving
Day through Friday. Temperatures are expected to moderate over
the weekend, but rain or a brief wintry mix, is also anticipated
to develop during the day Saturday.

&&

.NEAR TERM /THROUGH THURSDAY/...

Some light will be going on this morning.

However our main concern is a approaching band of snow squalls
across lake Ontario currently. This will move southeast across
the NY Thruway through late morning and into the Cortland area
eastward to around Cooperstown by early afternoon. A quick inch
of snow is expected to fall within about an hour with blowing
and drifting of snow as well. A few thunderstorms are also
embedded within the line as well. The RAP model has the best
handle based on mesoscale analysis this morning. Locations
further south and west will be further away from the best lift
and dynamics but will still see snow showers today.

415 AM Update...
A winter weather advisory remains in effect over portions of
our northern NY state counties through this evening.

Given the high volume of holiday traffic, we continue to remain
quite focused on this potential and it has been highlighted in
a hazardous weather briefing, which can be accessed by going to:
www.weather.gov/bgm/briefingMain.

Lake-effect snow bands will also be at play late in the
afternoon and into tonight, owing to significant cold air
advection and lingering low-level moisture. Flow orientation
favors Onondaga, Madison, and Oneida counties for the most
persistent lake snows late day into early evening, with
southern Onondaga, southern Cayuga, Cortland, Tompkins, and
maybe portions of Seneca, northern Tioga and northern Broome
Counties later tonight into Thursday morning on a NNW flow
(320-330 degrees). Accumulations tonight into Thursday morning
for these locales could range from 1 to 3 inches, with locally
higher amounts in narrow bands. The snow will be very dry and
fluffy, likely 20:1 liquid ratios. 850 mb temperatures are
still forecast to fall to around -20 to -22C by 12z Thursday,
along with sub 510dm 1000-500mb thicknesses...i.e. unprecedented
cold for mid to late November.

After midday highs in the upper 20s-mid 30s today, readings
will tumble in the afternoon behind the arctic front, ending up
well down into the 20s by sunset. By daybreak Thursday, air
temperatures will be in the single digits to lower teens, with
apparent temperatures (wind chills) below zero in many locales.
Portions of Oneida, Otsego, Delaware and Sullivan counties look
to see wind chills around 15 below for a time Thursday
morning...therefore a wind chill advisory has been issued for
these areas from 1 AM Thursday until noon.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
5 AM Update...
Record lows are expected by dawn Friday, but temperatures will
begin to moderate as we head into the weekend.

Under mainly clear skies, winds will go light/variable or calm
and temperature readings will free fall Thursday night with
ideal radiational cooling conditions. Lows by sunrise Friday
mostly in the single digits above zero but some of the typically
coldest drainage spots could even slip below. There is a little
bit of uncertainty that a thin layer of lake clouds could
persist for a time over part of the northeastern zones which
might prevent a full drop off in temperatures, but even so just
about all areas will get into single digits.

While still rather cold for Friday, it will also be crisp and
mostly sunny, with temperatures reaching into mostly the mid to
upper 20s. That will represent a 7 to 10 degree boost compared
to Thanksgiving highs. A quick drop into the mid teens-lower 20s
in the evening, will be followed by a gradual creeping up of
temperatures as high clouds begin to stream into the region
ahead of our next system.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
5 AM update...
Forecast adjusted for latest multi-model consensus. One trend
worth noting, is that it will take longer for precipitation to
move in Saturday; primarily afternoon into evening.
Temperatures thus appear to be warm enough by then for mainly
rain, though since this will be following a very anomalous
Arctic air mass we always have to be careful in case low level
cold air has trouble scouring out. One positive development in
this regard is that high pressure will quickly shoot east-
southeast off the coast of NJ-NY-Southern New England, instead
of being anchored over Northern New England. This is suggestive
of a quicker warm air advection which is more likely to support
all rain, instead of that second scenario which would be more
conducive to a initial period of wintry mix. We will continue to
monitor closely.

Previous discussion...
Saturday, low pressure moving into the mid Atlantic region will
spread precipitation across the area. The GFS is faster with
onset then the ECMWF so will mention a light wintry mix from I81
west during the morning but by afternoon temperatures modify
enough for just rain. The rain will continue into Saturday night
before tapering off. Highs on Saturday will be in the 40s with
lows Saturday night in the mid/upper 30s.

On Sunday area will reside between systems although scattered rain
showers are still possible.

Sunday night into Tuesday, a more significant system will track from
the mid west northeast across the Ohio Valley and into New England.
Another wet period looks likely Monday into Monday night. Highs
Sunday and Monday will be in the lower to middle 40s.

By Tuesday mainly scattered rain showers are expected behind
departing low. Highs will range from the mid 30s to lower 40s.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
Expect a mix of low end VFR and MVFR conditions early this
morning, through about 13-15Z. Should be mainly MVFR CIGS/VIS
at KSYR and KRME during this timeframe. West-southwest winds
are increasing between 10-20 kts.

A strong cold front will push across the terminals during the
late morning into the afternoon hours, bringing snow squalls
and WNW wind gusts of 25 to 35 knots. The best chance for
squalls will be north of the NY/PA border. However, a few
squalls may make it to KAVP toward 20-22z this afternoon.

Some of the snow showers will produce visibilities between 1/4SM
and 2SM, with ceilings falling to between 500 and 1200 feet.
Brief squalls could even produce +SHSN, with vis less than 1/4sm
for a short period of time.

Light MVFR lake effect snow showers continue into the evening
and overnight hours for the NY terminals, as KAVP becomes VFR.
WNW winds remain breezy between 10-20 kts., but then decrease
late at night to less than 10 kts.

Outlook...

Thursday...VFR, except for intermittent restrictions from lake
effect flurries KSYR-KITH-KELM-KBGM in the morning.

Friday...VFR.

Saturday/Sunday...Restrictions perhaps redeveloping in lower
CIGS and light rain.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...Wind Chill Advisory from 1 AM to noon EST Thursday for NYZ009-
     046-057-062.
     Winter Weather Advisory until 10 PM EST this evening for
     NYZ009-018-036-037.

&&

$$
SYNOPSIS...MJM
NEAR TERM...MJM/MWG
SHORT TERM...MDP
LONG TERM...MLJ/MDP
AVIATION...MJM